Troubleshooting Windows NT Add-On Subsystem for PM

• Microsoft Windows NT Add-On Subsystem for Presentation Manager, version 1.0

SUMMARY

This article contains the troubleshooting section from the Windows NT Add- On Subsystem for Presentation Manager documentation.

TROUBLESHOOTING

Following are some possible problematic situations with the Presentation Manager Subsystem and the workarounds for them:

A Presentation Manager Application Fails

to Run Properly on the Presentation Manager Subsystem

1. Make sure the application runs properly on native OS/2 version 1.3. Note that some OS/2 version 1.1 programs don't run on OS/2 version 1.3 and need to be recompiled and relinked.

2. If the Presentation Manager application fails at load time, it may be helpful to see if the Presentation Manager Subsystem issued an error message with the reason for the failure. To see such messages, you will need to invoke the offending application from a CMD window (otherwise, the CMD window created by the Program Manager disappears as soon as the application terminates). Please write down the error message and include it in your problem report to Microsoft.

3. Check if the problem you are experiencing appears in the Presentation Manager Subsystem Release 1.0 Bug List.

4. Take a look at the restrictions on OS/2 programs (see Volume One of the Windows NT Resource Kit, "Windows NT Resource Guide"). These restrictions apply to Presentation Manager programs as well. For example, the application may require a private OS/2 device driver (which can't run "as is" under the Windows NT OS/2 & Presentation Manager Subsystem).

5. The application may use NET API's not completely supported by the Windows NT OS/2 & Presentation Manager Subsystem - see NET API spreadsheet.

6. Make sure your Path and Os2LibPath variables are set properly. If your application is providing help files, check the Help variable as well. The way to inspect & modify these variables is by editing C:\CONFIG.SYS with an OS/2 or Presentation Manager editor. Note that Os2LibPath appears as LIBPATH in C:\CONFIG.SYS. For more details, please refer to the Windows NT Resource Guide chapter about the OS/2 compatibility (this chapter is provided with the Presentation Manager Subsystem Release 1.0 documentation).

• The OS/2 subsystem may fail to locate the application's DLL(s) (via the Os2LibPath variable).
• The application may fail to locate its help (.HLP) files.
• The application may use the wrong HLP file if another file with the same name appears first in the Path.

The Presentation Manager Subsystem is not Functioning Properly

For example:

• The Presentation Manager Desktop is not redrawn when you switch to it.
• Presentation Manager applications do not receive mouse or keyboard events.
• New Presentation Manager applications that used to work now fail to load properly.

1. Terminate the Presentation Manager Subsystem (PMSHELL and all Presentation Manager applications) by either:

   a. Try to close the Presentation Manager Subsystem from the Presentation

         Manager Task Manager (if it can be    invoked)
   
      b. If the above step fails, try closing the PMSHELL WIN32 iconized
         window or from the WIN32 Task List.
   
      c. If above steps fail, close all Presentation Manager applications
         forcefully, and then PMSHELL (see section 3.7.2)
   
   

2. After terminating the Presentation Manager Subsystem, restart PMSHELL. If this fails, kill the OS/2 Subsystem server (see section 3.7.2)

3. If step 2 failed, a reboot of Windows NT may be required

PMSHELL Fails to Start, Even After Rebooting Windows NT

Some of the Presentation Manager Subsystem files may have been corrupted. Try reinstalling the Presentation Manager Subsystem.

1. Terminate the Presentation Manager Subsystem (PMSHELL and all Presentation Manager applications) by either:

   a. Try to close the Presentation Manager Subsystem from the Presentation

         Manager Task Manager (if it can be invoked).
   

   b. If the above step fails, try closing the PMSHELL WIN32 iconized

         window or from the WIN32 Task List.
   

   c. If above steps fail, close all Presentation Manager applications

         forcefully, and then PMSHELL (see section 3.7.2).
   

2. After terminating the Presentation Manager Subsystem, restart PMSHELL. If this fails, quit the OS/2 Subsystem server (see section 3.7.2).

3. If step 2 failed, a reboot of Windows NT may be required.

Desktop is Locked

You can't switch away from the Presentation Manager desktop. The screen may be black at that time.

Check if Windows NT is still functional (press NUM LOCK and check if the indicator light is toggled): if it is, then please wait about four minutes.

After that time, the WIN32 may be restored, in which case you can terminate all Presentation Manager applications and PMSHELL (see "Forceful Termination," section 3.7.2). Otherwise, a reboot of Windows NT is needed.

PMSHELL Doesn't Come Up, Even After a Fresh

Installation of Presentation Manager Subsystem

This might be caused by the presence of a display adapter which the Presentation Manager Subsystem doesn't recognize. To overcome this problem please perform the following steps (after terminating PMSHELL and rebooting your system):

1. Start PMSHELL with the '/w' switch, i.e.:

         PMSHELL /w
   

   Please let PMSHELL come-up undisturbed (i.e. do not try to switch-away from it while it is starting and do not start WIN32 applications at the same time). PMSHELL will start seemingly as usual but after PMSHELL comes up and restores the Windows NT Desktop, the first switch back to the Presentation Manager Desktop will cause the Presentation Manager Subsystem to write a file with the proper video registers settings for your adapter under C:\OS2\VIDEOHW.DMP.

2. Shut down PMSHELL as usual.

3. From now on, PMSHELL should be able to come up as usual (i.e. without the /w switch): it will find that there is a file C:\OS2\VIDEOHW.DMP and use the values stored there in place of internal values.

• Another remedy to the above problem is to configure your Windows NT system to use the standard VGA display driver rather than the one for your display adapter. However, the resulting display resolution may be impractical.
• Note that the C:\OS2\VIDEOHW.DMP file may be copied to other systems with the same display adapter
• If you change the display adapter in your Windows NT system, the C:\OS2\VIDEOHW.DMP will no longer be appropriate: it is advised to delete this file (although the Presentation Manager Subsystem will detect the mismatch and ignore the file).
• Even if you successfully overcame this problem with the /w work-around, please notify Microsoft of the problem (indicating the display adapter & resolution) you are using.

Subsystem but the Presentation Manager Desktop Isn't Terminated

This situation may be caused by a Presentation Manager application which misbehaves upon shutdown and can be observed also under native OS/2 version 1.3. You need to terminate PMSHELL forcefully.

REFERENCES

Microsoft Windows NT - Presentation Manager Subsystem Overview, release 1.0