A: If you see problems with side-by-side assemblies, a detailed report can be generated using the SxsTrace tool. First,  start a trace by running this command:

sxstrace trace -logfile:sxstrace.etl

This returns the output

Tracing started. Trace will be saved to file sxstrace.etl.
Press Enter to stop tracing...

Run the application giving the error, then after it's complete, click Enter to stop tracing. Now generate an output from the trace:

 C:\>sxstrace parse -logfile:sxstrace.etl -outfile:sxstrace.txt

This returns the output

Parsing log file sxstrace.etl...
Parsing finished! Output saved to file sxstrace.txt.

Open the generated text file and the exact problem will be shown. Mine was as follows:

INFO: Parsing Manifest File C:\Program Files (x86)\Microsoft Office\Office14\WINWORD.EXE.

INFO: Manifest Definition Identity is winword,processorArchitecture="X86",type="win32",version="14.0.5123.5000".

INFO: Reference: Microsoft.VC90.CRT,processorArchitecture="x86",publicKeyToken="1fc8b3b9a1e18e3b",type="win32",version="9.0.30729.1"

INFO: Resolving reference Microsoft.VC90.CRT,processorArchitecture="x86",publicKeyToken="1fc8b3b9a1e18e3b",type="win32",version="9.0.30729.1".

INFO: Resolving reference for ProcessorArchitecture WOW64.

INFO: Resolving reference for culture Neutral.

INFO: Applying Binding Policy.

INFO: No publisher policy found.

INFO: No binding policy redirect found.

INFO: Begin assembly probing.

INFO: Did not find the assembly in WinSxS.

INFO: Attempt to probe manifest at C:\Windows\assembly\GAC_32\Microsoft.VC90.CRT\9.0.30729.1__1fc8b3b9a1e18e3b\Microsoft.VC90.CRT.DLL.

INFO: Did not find manifest for culture Neutral.

INFO: End assembly probing.

INFO: Resolving reference for ProcessorArchitecture x86.

INFO: Resolving reference for culture Neutral.

INFO: Applying Binding Policy.

INFO: Find publisher policy at C:\Windows\WinSxS\manifests\x86_policy.9.0.microsoft.vc90.crt_1fc8b3b9a1e18e3b_9.0.30729.6161_none_f480bfaef65491a5.manifest

INFO: Publisher Policy redirected assembly version.

INFO: Post policy assembly identity is Microsoft.VC90.CRT,processorArchitecture="x86",publicKeyToken="1fc8b3b9a1e18e3b",type="win32",version="9.0.30729.6161".

INFO: Begin assembly probing.

INFO: Did not find the assembly in WinSxS.

INFO: Attempt to probe manifest at C:\Windows\assembly\GAC_32\Microsoft.VC90.CRT\9.0.30729.6161__1fc8b3b9a1e18e3b\Microsoft.VC90.CRT.DLL.

INFO: Attempt to probe manifest at C:\Program Files (x86)\Microsoft Office\Office14\Microsoft.VC90.CRT.DLL.

INFO: Attempt to probe manifest at C:\Program Files (x86)\Microsoft Office\Office14\Microsoft.VC90.CRT.MANIFEST.

INFO: Attempt to probe manifest at C:\Program Files (x86)\Microsoft Office\Office14\Microsoft.VC90.CRT\Microsoft.VC90.CRT.DLL.

INFO: Attempt to probe manifest at C:\Program Files (x86)\Microsoft Office\Office14\Microsoft.VC90.CRT\Microsoft.VC90.CRT.MANIFEST.

INFO: Did not find manifest for culture Neutral.

INFO: End assembly probing.

ERROR: Cannot resolve reference Microsoft.VC90.CRT,processorArchitecture="x86",publicKeyToken="1fc8b3b9a1e18e3b",type="win32",version="9.0.30729.1".

ERROR: Activation Context generation failed.

End Activation Context Generation.

It turns out that somehow my Visual C++ 2008 redistributable installation had become corrupt. The solution was to uninstall every version of the Visual C++ 2008 redistributable installed on my system.

Then I had to reinstall from Microsoft. After reinstallation, my problem was resolved.

Visual C++ 2008 Redistributable
Visual C++ 2008 SP1 Redistributable
Visual C++ 2008 SP1 Redistributable ATL Security Update  

 Read more FAQs on all things Windows--and beyond--at John Savill's FAQs.