http://www.howtogeek.com/178826/how-to- ... ator-mode/
I've been getting the odd error with MSI files that give a 2502/2503 error when running. The work around is to run then from an Admin CMD window. Try talking a client through that. The above link shows where a simple reg edit goes to allow for a right-click option on MSI files.
Here's the shortform: