On an Exchange 2007 server, the following event may show up in your Eventlog:
Event Type: Error
Event Source: SideBySide
Event Category: None
Event ID: 59
Time: 12:30:39 AM
Generate Activation Context failed for C:\WINDOWS\WinSxS\amd64_Microsoft.VC80.MFC_1fc8b3b9a1e18e3b_8.0.50727.762_x-ww_6E02DFE5\MFC80U.DLL. Reference error message: The referenced assembly is not installed on your system.
The solution for this error is to install Microsoft Visual C++ 2005
- Microsoft Visual C++ 2005 Redistributable Package (x86)
- Microsoft Visual C++ 2005 Redistributable Package (x64)
The install does not require a reboot, neither it stops services (except the MsiInstall service). Therefore, as long as your server is an dedicated Exchange 2007 server, you can safely install Visual C++ 2005 in a production environment.