Installing to any drive other than C: Contributed by Srinivas Kyatham if you have to install appllications to anyother Physical Drive (not network drive) you can do so in the following way. default INSTALLDIR : C:\Program Files\Dir1 Change to D:\Program Files\Dir1 1. In the MSI Script create a custom action In "User Interface" just after "Cost Finalize" "Set Directory" give it a Name , choose the directory by browsing to ProgramFilesFolder\Dir1 and in the third Blank Space enter "D:\Program Files\Dir1" 2. Create the same Custom action in "Execute Immediate" just after "Cost Finalize" also This installation works fine as long as D: is a valid Drive, it does not work on drives that were created using "Subst.exe" Command.