When you change the mode from private to standard, you may get this error: “An unexpected MAPI error occurred.”. If you click on “More details”, there stand: ”Failed to map vDisk, no Driver.”.
The solution to this problem could be, changing the the Microsoft Volume Licensing, from KMS to ether None og MAK. And then push the OK buttom. If its work you can just change the Microsoft Volume Licensing back to KMS.