While trying to install Visual Studio 2005 one of my client was getting error "Installing to mapped drive is not supported"

Complete Error

At least one component has an install path set to a mapped drive. Installing to mapped drive is not supported

Cause: This issue is seen when the C:\Program Files\Common Files location in the registry is set to a Mapped or a Share Drive

Resolution: Registry Edit is require for this

WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall Windows. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk.

The registry key to modify is:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion

CommonFilesDir: This key should point to C:\Program Files\Common Files