Hi,

short post after Summer vacation 🙂 A customer had the problem that he couldn’t install msxml4 sp3.

During installation the setup could not register type library C:\Windows\SysWOW64\msxml4.dll.

The reason was that he had disabled application compatibility engine by policy via registry:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\AppCompat]
"DisableEngine"=dword:00000001

or by Group Policy Object Editor

Solution is to enable the Application Compatibility Engine.

c:\> reg add " HKLM\SOFTWARE\Policies\Microsoft\Windows\AppCompat" /v DisableEngine /t REG_DWORD /d 0 /f

or by GPO Editor

Michael