The default is C:\ISTS.  If that doesn't exist or you can not access it,  then it uses the settings in SD-Q.  so yes it will work but be careful.  If you are using terminals, you will have problems.
 
Another option is to create a share at the rtoot of H: and map it to C:
 
The reason it is drive H is because it came from another computer and the signature in block 0 doesn't match.  Since developers expect the OS to be on drive 0 and mapped as drive C, you may have problems with other applications.  The best way to fix this is to backup the drive (You can use windows File and settings transfer wizard and go to a server), go into drive manager, change the drive letter to C:, reinstall windows and applications then restore the data.
 
Hope it helps,
 
 
Tim