One suggestion I found that shouldn't hurt anything is to try Unregistering the exe then Registering again.
Open a command prompt and type
and hit Enter
It should pop up a usage dialog box for Regsvr32.exe
If it does, you know it's in the path. So just click OK to close the dialog.
Find "msiexec.exe" on your system.
Open an administrative command prompt in that folder and type
regsvr32 /u msiexec.exe
It should say Unregister of msiexec.exe succeeded.
If so then type the same command but without the "/u" switch
It should say succeeded again.
Now try the install again.
Regsvr32 adds and removes registry entries for COM libraries and programs.
RPC error is a COM error. It can mean that it cannot find the program because when it looks in the Registry the correct info is not there. In any case it's already broken. This won't hurt it.
Here's a post roughly related to your problem: http://answers.microsoft.com/en-us/w...1d77702?auth=1