From: Rich Gauszka 

Mike N. wrote:
> On Sun, 18 Feb 2007 09:00:05 -0500, mike  wrote:
>
>> Activation context generation failed for
>
>   WHOAH!   Enter Ehanced Reduced Functionality Mode....

or a problem with Visual C++ 8.0 runtime files and Vista?

http://blogs.msdn.com/astebner/archive/2007/01/09/problems-with-custom-actions-
that-depend-on-the-visual-c-8-0-runtime-files-on-windows-vista.aspx

I recently heard about a couple of scenarios that were causing problems for
folks creating MSI-based setup packages.  In one case, the developer was
installing a service and attempting to start it using the ServiceControl
table, but it failed when running setup on Windows Vista.
  In another case, the developer was attempting to self-register a DLL
and it failed when running setup on Windows Vista (such as in the scenario
described here).

In both of these scenarios, the error message "Activation context
generation failed for " was logged in the event
log.  The error code seen in these scenarios was -2147010895, which is
0x800736B1 in hexadecimal and translates to ERROR_SXS_CANT_GEN_ACTCTX.

In both cases, the binaries in question had a dependency on the Visual C++
8.0 runtime files, and the MSI included the MSMs to install the VC 8.0
runtime files as part of the same setup.

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