In my case, the %commonprogramfiles% path in the registry key HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\ was pointing to "<network drive>:\ProgramFiles\Common" which is not a valid path. What I did was:
1. Change the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\CommonFilesDir key to point to "C:\Program Files\Common Files"
2. Reboot the server
3. Restart the software installation.
This may occur when installing new software - the installation will abort saying "Invalid Drive Letter <letter>:". The solution is to change some registry values. Verify that the values under:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders use valid drive letters. If there are invalid drive letters, change them to point to valid drives.
I was getting an event id error of 11327 from the msiInstaller that was stating there was an invalid H:\ drive while I was trying to uninstall a program. After looking on the Internet I found out that this could come up as any drive letter and in my case it happened to be the H:\ drive. To fix this I had to check registry entries in 5 places to make sure they were not pointing to this drive for install files. The registry keys were:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders
Make sure none of the values in these 5 keys are pointed to the drive of the error message. I had two of them that I had to change. Once I made the change I no longer got this error message.
This error ocurred when I tried to run the Office installer over remote desktop on a terminal server after running "change user /install". Installing while logged into the console worked fine.