Microsoft .NET Framework 1.1 Service Pack 1 / exception error

Installation of Microsoft .NET Framework 1.1 Service Pack 1 returns the
following error message:

SL1.tmp - Common Language Runtime Debugging Services

---------------------------

Application has generated an exception that could not be handled.



Process id=0x98c (2444), Thread id=0x640 (1600).



Click OK to terminate the application.

Click CANCEL to debug the application.



OS is XPpro SP2. All other patches did work just fine.

I tried an uninstall of .net 1.1 runtime followed by a full install of the
redistributable package of .net environment 1.1.

Any suggestions?

Joachim