|KB2984972 May Cause Problems with 32-bit App-V 4.6 Applications Using splwow64.exe to Print on 64-bit Windows 7|
|Written by Darwin Sanoy|
|Wednesday, October 29, 2014 7:24pm|
Once splwow64.exe is started - all 32-bit applications will use the same instance to print - until it timeouts and unloads itself. So once an App-V 4.6 packaged application starts splwow64.exe it affects all 32-bit software that attempts to print - whether or not it is an App-V packaged application.
Also, if the in memory instance of splwow64.exe is was started by a non-virtualized application - it prints fine for both virtualized and non-virtualized apps.
From a procexp.exe stack trace (with symbols configured), it appears that splwow64 starts to spin while waiting for an API "WaitforLsmStart" in winsta.dll. LSM -= local security manager. Since KB2984972 was the only one of six recent security updates we applied that played with LSA (Local Security Authority) files - it was isolated for testing with it uninstalled.
These are the kinds of skills we help you get started with in Windows Application Packaging, Provisioning and Troubleshooting Engineer Bootcamp (ENG-55) which was recently held in Utrecht, Netherlands.