I can't get root folder. Not only C:, Other partition (F:) or some mapped share folder (S:) behave same, but some mapped drive have no problem.
Slash and backslash get same result (good).
Extra slash at the tail make the result to full path.
Another issue is I can't get C:\Temp with error 2. I have same error for Temp2 and Temp3 those I made for test. There is not Temp1, then the error is 3.
There are other folders getting error2, existing "ProgramData" etc.
c:\bin got another error, -1.
I tested on Windows7 with local user in administrators group, so there shouldn't be permission issue.