I have been having a similar problem, and it looks as though this is the solution to both of our problems.
http://www.winability.com/how-to-make-elevated-programs-recognize-network-drives/
The link in the article to the Microsoft KB is for an article relating to Windows 7 / Vista, however other answers on the Microsoft site relating to Windows 8 are the same.
**In short: UAC (User Account Control) is the problem in this situation as it tries to separate the user an administrator for greater security.