Known issues commonly reported

Wikis > ArcaOS > Known issues commonly reported

Before opening a fresh ticket, please review the README files in the root of the installation ISO and installed to \sys\doc\ArcaOS, paying particular attention to the Known Issues sections. Additionally, per the Best Practices wiki page, please search the bug tracker for similar issues before reporting another instance of the same condition. Duplicate tickets cause more work for everyone.

This page is meant to supplement the README with the latest information available concerning the most commonly reported issues of which we are already aware.

On this page

Inability to boot into the installer before 5.0.7
Clipped text in some installer dialogs at lower resolutions
Lack of functional scrollbar on License page of installer
Trap 8 booting ArcaOS before 5.0.5
DOS and/or WIN-OS/2 sessions
USB device issues
Hidden/missing disk controllers
Serial ports
IBM File and Print Client issues
Samba Client and Server issues
High CPU utilization and/or unexplained hangs
File system case retention vs case sensitivity
Mozilla application startup issues with older systems
Multimedia issues
Update-related issues

Inability to boot into the installer before 5.0.7

Certain systems reported “Failed to restore A20 gate” while booting from the ArcaOS installation medium (DVD, ISO, USB, and local partition). This condition has been corrected as of ArcaOS 5.0.7, and the A20 Gate detection should no longer be an issue.

Clipped text in some installer dialogs at lower resolutions

Bear in mind that every effort has been made to have the installer pages legible at all expected resolutions. To aid in this, it is possible to reduce or enlarge the font size. Two points to remember:

    • On VGA-only (640×480), Small font size should be readable.
    • On 800×600, Small and Medium font sizes should be readable.

Font sizes larger than above at the resolutions shown cannot be guaranteed readable.

Lack of functional scrollbar on License page of installer

It is possible that with a very high display resolution, the license text on page 2 of the installer fits entirely within the viewable area, obviating the need for scrolling. Unfortunately, as the text must be scrolled to the bottom in order to enable the checkbox to indicate agreement with the license terms, it is not possible to proceed with the installation.

Clicking on the down button at the bottom of the scrollbar area should enable the checkbox.

Arca Noae is looking to revise the logic for enabling the checkbox in a future release.

Trap 8 booting ArcaOS before 5.0.5

If a trap 8 occurs when attempting to boot ArcaOS versions prior to 5.0.5 from the hard disk, try booting from the installation media, and using the text editor from the System Management console, comment the two lines in \OS2\BOOT\SNOOP.LST on the boot volume by inserting “;” in front of each. Save the file, shutdown and reboot to the hard disk.

DOS and/or WIN-OS/2 sessions do not work

This is a known condition on many newer systems. It is mentioned in the README in the list of known issues. Generally, this is due to an incompatibility in the BIOS of the system with the DOS VDM code in ArcaOS (inherited from IBM’s OS/2 Warp 4).

Arca Noae is continuing to work on addressing this (and other causes of failure of DOS sessions to start).

Some possible workarounds:

Modify the VSVGA.SYS line in CONFIG.SYS to include the following parameter:

DEVICE=N:\OS2\MDOS\VSVGA.SYS /int10textgrfxsafe

With the above change, it may be necessary to append the following to AUTOEXEC.BAT (located either in the root directory of the boot volume or where specified for the DOS session object):

mode co80

Another option, when full screen sessions work but windowed ones do not, is to open a full screen session first, and then press Alt-Home to switch it to a windowed session (this only works for DOS sessions, not OS/2 full screen and windowed sessions).

The main tracking ticket for progress on this issue is #1193.

USB device issues

Issues pertaining to inability to access USB-connected drives, often involving USB-attached DVD drives, where the installation disc starts to boot and then prompts for insertion of the medium (which is obviously already installed) are often the result of unsupported (non-standard) USB controllers, devices, or devices connected through intervening hubs.

To be clear, it is not always easy to tell which systems have standards-compliant controllers driving their USB ports. ArcaOS releases prior to 5.0.5 require the presence of an EHCI (USB 2.0) controller driving the USB 2 port where the device to be accessed is attached. ArcaOS 5.0.5 is fully xHCI (USB 3) aware, but again, the controller and device must be standards-compliant and hubs (attached to any port or controller) may be problematic.

Note that this same behavior will be observed for USB-attached keyboards and mice. When so-called legacy support is enabled in the system BIOS, USB devices are handled by the system BIOS directly. Once the device driver has been loaded, however, control is handed off to the software driver. If the software driver lacks support for the type of USB controller to be driven, then nothing has control of USB, and these ports, while still allowing current to flow (they work for charging and powering other devices, of course, with or without a software driver) are effectively ignored by ArcaOS. This is why keyboards will work for preboot selection during installation, for example, but upon entering the installation environment following boot, no input is possible.

Conversely, if no USB keyboard or mouse input is available in the preboot environment, it is likely that these devices will not be available to the booted system, either. Verify that Legacy USB support is enabled in the BIOS.

Possible workarounds

If this is a desktop system, install a standards-compliant controller card. Often, these cards include 2 or 4 ports on the bracket and perhaps an internal port or header, as well. This allows them to supplement the onboard USB controller present in the system. Connect all devices needed to be accessed by ArcaOS to this standards-compliant adapter.

Portables offer greater challenges for workarounds, though ExpressCards are available for systems with compatible slots.

Selecting Boot from hard disk from USB stick boot menu reboots to USB stick

This is a common issue on some hardware configured to boot from USB devices first. The reboot attempt is directed to the first hard disk, but as the USB stick appears to the system to be the first hard disk, boot is attempted from that, instead. This is not a software defect, nor anything which could possibly be addressed in any universal way within ArcaOS or its installation software.

Possible workarounds

At the end of phase 1 of an install or update, when the screen goes black during the reboot sequence, physically remove the USB stick. Once the system starts to boot from the hard disk (white “boot blob” visible in the upper left corner of the screen), reinsert the stick. This should allow the USBMSD driver to locate it during the boot sequence and to be able to mount the ArcaOS installation ISO stored on it.

Some systems provide a key to press to access a temporary boot device menu. If available, press that, select the hard disk, and allow the system to boot normally.

You may need to perform this same procedure (either the manual removal/reinsertion or accessing a temporary boot device menu) for subsequent reboots during the installation or update. When the installation or update is complete, be sure to properly eject the stick.

Cannot access USB diskette drive

By default, ArcaOS installs without support for USB-attached diskette drives. To configure this for your system, see the relevant information here.

No audio from USB CD drive

See the relevant section on this page.

Hidden and/or missing disk controllers

Certain Intel-based systems equipped with Intel® Volume Management Device (VMD) technology may hide NVMe and SATA controllers from the OS when enabled. This results in the ArcaOS installer reporting that there is no disk controller in the system.

Possible workarounds

Disable VMD in BIOS setup. This will render RAID configurations inoperative in systems so equipped, so may not be possible in multi-boot situations without backing up and restoring existing partitions. Once VMD has been disabled successfully, however, any available controllers should become visible.

Phantom serial port devices

It is possible that the installer will recognize an Intel Manageability Engine serial port (KT Controller) device as a normal serial (COM) port, and install the PSCOM.SYS driver (and matching VCOM.SYS driver, if DOS support is selected). These ports are not usable by ArcaOS. Upon booting, the system will generate a SYS1201 error attempting to load PSCOM.SYS (and again, for VCOM.SYS, if specified, as this depends upon a valid OS/2 COM port driver being loaded).

Possible workarounds

If there are no other valid serial ports in the system, press <Enter> to acknowledge each of these when presented during boot. Edit CONFIG.SYS to comment out each of these (insert “REM” at the beginning of each affected DEVICE= line). Save the file and reboot.

If there are valid, enabled serial ports in the system, it will be necessary to add the proper entries to \OS2\BOOT\PCIDEV.TBL to force PSCOM.SYS to ignore the KT controller device. See \OS2\BOOK\COM16.TXT for more details.

IBM File and Print Client issues

IBM File and Print Client connectivity issues to Windows 7 and newer

When using the NetBIOS-based IBM File and Print Client to connect to Windows 7 and above, file transfers may fail with SYS0240. ArcaOS versions prior to 5.0.3 utilized the OS/2 Warp standard configuration for multiplexed SMB (Server Message Block) reads and writes. Once a multiplexed read or write is attempted from or to one of these newer Windows versions, the Windows system resets the connection.

The solution is to set bits 14 and 15 of the wrkheuristics parameter in \IBMLAN\LANMAN.INI to 0 to disable multiplexed reads and writes. This is now the default in ArcaOS 5.0.3 and above, and should have no negative impact on performance.

This change affects native NetBIOS and NetBIOS over TCP/IP equally.

More information may be found here.

Arca Noae recommends the use of Samba for file sharing between ArcaOS and other systems, including Windows, Linux, and other ArcaOS systems. Samba supports enhanced authentication protocols, encrypted file transfers, and pure-IP connectivity (no NetBIOS required).

Restoring default IBM File and Print Client user accounts

There may be situations where recovery of the existing user accounts file (NET.ACC) is either impossible or undesirable. It is possible to restore the original (default) file from the ArcaOS installation medium:

  1. Reboot
  2. Shut down the requester
  3. Mount the ArcaOS installation DVD or ISO
  4. Extract the default NET.ACC

    (where X: is the drive letter assigned to the ArcaOS DVD or ISO and C: is the drive where NET.ACC is located)

  5. Select LAN Logon (Workgroup) and enter the default username/password (USERID/PASSWORD) which will start the requester
  6. Open Sharing and Connecting and add user accounts and groups as required

Arca Noae highly recommends creating an alternative administrator account and after logging out and back in with the new account, deleting the USERID account.

Inability to map to File and Print shares from Samba clients

Later versions of Samba, including versions shipping with ArcaOS, are gradually phasing out support for the older authentication and SMB protocols used by the IBM File and Print Client and other older servers and devices (including the Samba 3.6-based server component shipping with ArcaOS). As of ArcaOS 5.0.5, Samba 4.11 requires the following to be added to %ETC%\samba\smb.conf in the [global] section in order to connect to these shares:

client min protocol = NT1

This will force client protocol negotiation to start at the NTLM dialect (SMB1) and not the default of SMB2_02, and should allow Samba connections to be established to these shares.

Note that the typical error reported for such a failure to negotiate a common dialect is error 59.

Normally, upon first run of ArcaMapper, when the client min protocol has not been lowered to NT1 to present a Protocol Compatibility warning panel, advising of this, and offering to change the setting. If not making the change from the warning panel, this change may be made on page 2 of the Global settings tab or set manually by editing smb.conf as described above.

Loss of User and Group tabs in Sharing and Connecting object

This may happen if all administrator accounts have been deleted. While it is not normally possible to delete the last remaining administrator account, creating a new administrator account while logged in as the existing one and subsequently deleting the existing administrator account will cause the new account to not be saved, resulting in all administrator accounts being lost.

To recover, follow the procedure above to restore the default NET.ACC file and reconfigure accounts.

Samba Client and Server issues

Initial configuration of Samba Server (ArcaOS 5.0.x)

Under certain conditions, the initial configuration of Samba Server using the Simple Samba Configuration Center in the Samba Server desktop folder as included with ArcaOS 5.0.x does not result in a working setup. Symptoms of this condition include the inability to authenticate to the server to administer users and groups and the Samba Server daemon (smbd.exe) stopping immediately after startup (this may be seen when using the Samba Status Monitor GUI tool).

To properly initialize the Samba Server configuration:

  1. Ensure that the Samba Server daemons are stopped (nmbd.exe may continue to run even when smbd.exe has stopped). To do this, use the Stop Samba server object in the Samba Server desktop folder.
  2. Open a command prompt and delete the wheel group, if it exists:
    groupmod -x "wheel"

    (If you receive a message that “wheel” is invalid – cannot remove, this indicates that the wheel group is not present. Continue with the rest of the procedure.)

  3. In the Samba Server desktop folder, right-click the object for the Simple Samba Configuration Center, and select Properties.
  4. Ensure that /Install is the only option in the Parameters box. (If this utility has been run previously, the parameter will have been changed to /config, otherwise, it should already say /Install.)
  5. Close the Properties notebook and start the Simple Samba Configuration Center. It should present an Installation mode dialog. Select the following options:
    1. Erase current “smb.conf” and create a new one.
    2. Erase current “Backend” and create a new one. (available after checking the above)
    3. Install libraries using YUM.
  6. Click Continue and allow the process to begin. (If you receive an error 32 deleting <drive:>\<path>\gencache.tdb, you may safely ignore it and dismiss the message box. This implies that one or both of the Samba Server daemons may still be running and not fully stopped per step 1, above.)
  7. When prompted, enter a password for root and confirm it. (IMPORTANT: if “Erase current Backend and create a new one” was not checked, this dialog will not be presented.)
  8. Leave the default backend of “tdbsam” in place or select “smbpasswd” (tdbsam is preferred, but for small setups, smbpasswd is fine and more portable – tdbsam cannot easily be copied to a different server).
  9. Leave “Server type” set to Standalone.
  10. Set “Workgroup/Domain” accordingly.
  11. Click “Create Samba default configuration” to continue.
  12. Click OK after reading each message box presented.
  13. Click Start to start the Samba Server daemons.

If the wheel group has been removed as directed in step 2, above, the daemons will start normally. Close the Simple Samba Configuration Center.

Open the Samba Users and Groups object. Log in as root with the password set in step 6, above. Select the User account, and click Create (not Edit). This will create a matching Samba account for User. Set options as desired. Create additional users as needed.

Manually creating the Samba root and guest accounts

If you are unable to log into the Samba Users and Groups object as root, you will need to add root to the Samba users. To do this from a prompt (usually means that something went awry with the recreation of the backend):

  1. Change to the Samba server directory (X:\Programs\Samba).
  2. Run:
    smbpasswd -a root <Enter>
  3. Provide a password for root and confirm.
  4. To add the Guest account (no password):
    smbpasswd -a -n guest <Enter>

Volume persistence is enabled by default in Samba Client

By default, the current volume configuration is automatically saved as volumes.cfg to the \Programs\NDFS directory, and its contents will be restored at the next system start. While considered a convenience feature, this may pose a security risk in sensitive environments.

To disable this feature, comment the PersistentVolumeConfigurations line in \Programs\NDFS\ndctl.cfg:

#PersistentVolumeConfiguration = volumes.cfg

After the next restart, the volume configuration will not be restored.

High CPU utilization (one core) or lockups on multi-CPU systems

Not all software is “SMP-safe” or even “SMP-aware.” This is particularly true of older software written for Warp 4 or earlier versions of OS/2, when only servers had multiple CPUs. If you experience abnormally high CPU utilization on a multi-CPU or multi-core system when running a particular application, this could be the cause.

Possible workarounds

Before opening a trouble ticket, try changing the PSD=ACPI.PSD line in CONFIG.SYS to read:


Save the file, reboot, and retry the failing application. If this seems to avoid the problem, please include this information in your trouble ticket. In some cases, older applications may be patched to address such shortcomings. For third-party applications, it is best to contact the maintainer/publisher of the application to request a fix.

File system case retention vs case sensitivity

OS/2 is by design a case-insensitive operating system. Its native filesystems (HPFS and JFS) support case retention, so when opening MyFile.tXt and saving it to an HPFS or JFS volume, the file will be saved as MyFile.tXt. However, this does not mean that in the same directory mYfILE.TxT may also exist. To OS/2, these are the same file.

The situation becomes more complicated when accessing remote filesystems via Samba which are, in fact, case-sensitive as well as case-retentive. On a Linux system, for example, it is perfectly acceptable to have myfile.txt and MYFILE.TXT coexisting in the same directory, and to a Linux system, these are indeed unique files. The issue for ArcaOS, however, is that if both files are listed, opening the lower case one and saving it may result in the file with the uppercase name being overwritten. This is because internally, both the OS/2 kernel (and the ArcaOS kernel, by extension) and the Workplace Shell will “upcase” the filename. Thus, ArcaOS appears blissfully unaware of what file was actually opened.

Possible workaround

Ensure that filenames are unique per OS/2 local filesystem requirements before editing and saving them on remote volumes which are otherwise case-sensitive where such filenames would not conflict on the host system.

Mozilla application startup issues with older systems

The builds of Firefox, Thunderbird, and SeaMonkey delivered with ArcaOS 5.0.5 and later 5.0.x releases require a CPU supporting SSE2 instructions such as Pentium M, Pentium 4, or Athlon64 (or newer) and will crash when attempting to start on an older system such as a Pentium III.

Possible workaround

Until such time as these components are packaged as RPM, and the proper arch (i686) may be selected for install, download an i686 build of the desired application from this page (for Firefox) and/or from this page (for Thunderbird and/or SeaMonkey). Be sure to select a version which is at least at the level delivered with ArcaOS 5.0.5 (Firefox 45.9.0, Thunderbird 45.8.0, SeaMonkey 2.42.9). Once downloaded, follow the procedure below:

  1. Open the application’s desktop folder.
  2. If XXTurbo Uninstall is available in the folder (where XX is either FF, TB, or SM), run it, and select the option to uninstall.
  3. Open a command prompt.
  4. Rename the application directory, e.g.:
    ren X:\Programs\firefox firefox-p4 <Enter>
  5. Unzip the downloaded version to the X:\Programs directory.
  6. Ensure all files in the newly unzipped application directory are writable, e.g.:
    attrib -r X:\Programs\firefox /s <Enter>
  7. If you ran XXTurbo Uninstall in step 3, you may re-run it.
  8. You may delete the original application directory.

Multimedia issues

No desktop sounds are heard

Most systems should work well with the Uniaud Universal Audio driver. However, some systems may load the driver properly yet produce no audio output. Sometimes, these issues are mixer related. Refer to the Uniaud wiki for further information including debugging steps.

Possible workarounds

Try adjusting mixer settings with unimix.exe at a command line. For help with unimix’s syntax, run it without parameters. Parameter IDs, counts, and values differ from chipset to chipset, so you must get a listing of available IDs, counts, current values, and value ranges before making changes (use the -list parameter for this). If you find a set of parameters which work every time, simply add the commands to STARTUP.CMD in the root of the boot volume to have these applied at each boot.

Consider installing a separate (or different) sound card.

Updates to Uniaud are in process as of late 2020. If your audio hardware (including the mixer device) is not currently supported, it may be in a future release.

Uniaud is a joint Netlabs/Arca Noae project, with release builds and commercial support provided by Arca Noae for those with subscription services, and with most experimental development taking place at Netlabs. You may track the progress of this work here, and you may provide financial sponsoring for Netlabs in our store.

CD player produces no audio output

ArcaOS provides two separate CD player applications located in the Multimedia folder:

  • The player provided by the CW-MM Classes (objects titled CD-Audio Drive X: and the Media Player template); and
  • The base OS/2 player titled CD Player (Classic)

Possible workaround

The CW-MM Classes player currently does not support digital transfers, whereas the Classic player does. As almost all modern internal CD and DVD drives and all USB-connected drives utilize digital transfers (no separate analog audio cable), try using the Classic player.

Updates are in process for CW-MM Classes, among them support for digital transfers.
The CW-MM Classes are a Netlabs project. You may track the progress of this work here, the digital transfer enhancement request here, and you may provide financial sponsoring for Netlabs in our store.

Cannot play MP3 files

ArcaOS does not ship with an MP3 codec, due to still-not-quite-settled patent issues. An MP3 codec is available from Hobbes, however. This is documented in the MP3_INFO.HTM document located in the Multimedia desktop folder. (N.B.: Due to a reorganization of files in the Hobbes archive, the link to the MP3 codec in MP3_INFO.HTM in releases of ArcaOS 5.0 through 5.0.7 is broken. Please use the link above to access the codec.)

Update-related issues

Watch this space for confirmed issues and possible workarounds relating to the update facility in ArcaOS. Also see this page for update troubleshooting tips.

Unable to map Samba shares after updating to ArcaOS 5.0.4 and above

If Samba shares were being properly mapped prior to the update, the most likely cause of the trouble is a mismatch between the NetDrive plugin version installed and the Samba client library. This may occur if one is able to be updated but the other is not, for some reason.

Things to check

Examine the content of X:\Programs\NDFS\ndctl.log (where X: refers to the drive where the relevant Programs directory is located). A properly initialized Samba plugin will be listed as:

[ ndpsmb] (level 2) plugin has been loaded.
Initialization completed. The control program is running.


whereas a mismatch will report a failure to load, as in this example (note the name of the unloadable module):

NDF0033: The system can't load the module: SMBCLN49
NDF0029: [ ndpsmb] plugin has not been loaded.
NDF0007: The system error is SYS0002
Initialization completed. The control program is running.


(In this case, the plugin was updated, but the Samba client RPM package was not, and thus, smbcln49.dll was not installed.)

Similarly, if the plugin was not updated but the Samba client package was, the older plugin will report:

NDF0033: The system can't load the module: SMBCLN47
NDF0029: [ ndpsmb] plugin has not been loaded.
NDF0007: The system error is SYS0002
Initialization completed. The control program is running.


The resolution is different depending upon whether your problem is the first case or the second. In any event, either of these points to an installation which encountered difficulty finishing. In the first case, a good logfile to check would be X:\VAR\TEMP\3_YUMUPD.L2, where YUM errors are written during the update process. In the second case, check X:\VAR\LOG\1_GENUPD.L2 for entries pertaining to NDPSMB.ZIP.

Possible resolutions

In the first case above, the YUM update process likely did not complete due to an error reported in 3_YUMUPD.L2. The inability to locate a package required to update an installed package for which one of its dependencies is being updated is one possible cause (e.g., a development package which depends upon the base package; the ArcaOS On-Disc Repository contains the base package but not the development package). Use Arca Noae Package Manager to update the package reported in the error, and run the ArcaOS update procedure again (yes, you read that correctly: after updating the troublesome package, exit Arca Noae Package Manager and reboot to the ArcaOS installation medium to re-run the update).

Once the update is complete, again examine 3_YUMUPD.L2 for any errors related to package dependencies. If there are none, there is one final task required to resolve this problem. Follow the steps here to access the ArcaOS On-Disc repository. Go to the Available Packages list, and install the samba-client package. Disable the on-disc repository, remove the ArcaOS installation medium, and reboot.

The second case may be more difficult to fully resolve. If the plugin was not updated for some reason, a trouble ticket is probably warranted, however, it should be possible to at least update the plugin manually to restore Samba share mapping. To do this:

  1. Ensure that the NetDrive Control Program is not running. You may do this from within ArcaMapper (File | Control daemon > Disable).
  2. Mount the ArcaOS installation medium, and unzip \CID\SERVER\ARCAPKG\NDPSMB.ZIP to X:\Programs\NDFS, overwriting the matching files in the ndplugs subdirectory. (Note that X: is used here to refer to whichever drive is the actual target.)
  3. Start the NetDrive Control Program. From within ArcaMapper, this is File | Control daemon > Enable.

Verify that the plugin has been loaded by examining the content of X:\Programs\NDFS\ndctl.log, as discussed above.

Another common failure to connect to hosts utilizing older protocols is discussed above, under IBM File and Print Client and Samba issues. This situations may occur following an update to the Samba client components where support for older protocols is being phased out over time, requiring more customization of the smb.conf to allow for the less secure authentication protocols and Samba dialects. Once ensuring that matching files are indeed in place, this is the next place to look for the cause of such failures.

Network Adapters and Protocol Services applet not updated (ArcaOS 5.0.5)

Due to a minor packaging issue, the new NAPS 1.1.7 package in ArcaOS 5.0.5 is not applied during an ArcaOS update. While it is possible to apply this from the installation media (the NAPS.WPI package resides in \CID\SERVER\ARCAPKG on the ArcaOS ISO), the best fix is to just download the updated component as a self-extracting installer from the ArcaOS order details page. This will ensure that the proper version is recorded in the WarpIN database for future updates.

COMSPEC environment variable is left commented in CONFIG.SYS (ArcaOS 5.0.6)

To ensure a working environment for the update procedure, the


line in CONFIG.SYS is commented (REMmed). We have seen instances where this is not restored at the conclusion of the update. Manually remove the “REM” preceding that line in CONFIG.SYS. This has been addressed for future ArcaOS releases.

This entry last updated: by Lewis Rosenthal