I just tested in the lab and it works fine using:
1. Edit VM settings and increase the size you wanted
2. Access Computer Management->Storage->Disk Management
3. If you don't see new space show up you click on "More Action" and Scan then it will show new space
4. Right click on the C:\Windows partition and choose "Extend Volume" and then just click "Next" and "OK" and it should show up fine with new space assigned.
Quick and easy! Thanks all