Activation context generation failed for "somefile.dll".Error in manifest or policy file "Microsoft.VC90.CRT\Microsoft.VC90.CRT.MANIFEST" on line 4. Component identity found in manifest does not match the identity of the component requested. Reference is Microsoft.VC90.CRT,processorArchitecture="x86",publicKeyToken="1fc8b3b9a1e18e3b", type="win32", version="9.0.21022.8". Definition is Microsoft.VC90.CRT,processorArchitecture="x86",publicKeyToken="1fc8b3b9a1e18e3b", type="win32", version="9.0.30729.4148". Please use sxstrace.exe for detailed diagnosis.
If the file in question is a DLL, then this message means that the executable that depends on this DLL uses a different version of the CRT (9.0.30729.4148 in this case) than the DLL. The message is logged because the version of the CRT required by the DLL (9.0.21022.8) cannot be found in the specified directory.
You will either need to
* install the missing version of the CRT
* get a different version of the DLL (that requests the same version of the CRT as the EXE)
* correct the manifest of the executable to request the same version as the DLL