Remove disk letter assignment in Windows

Sometimes an OEM or system reserved partition may pick up a drive letter through Windows update where it shouldn’t have one, or a customer gets “hands-on” and does it on their own not knowing what they’re doing. OEM and System reserved partitions should not have drive letters, primarily because it confuses the customer.

The easy way

Try the easy way first:

1. Open Disk Management
2. Find the OEM or System Reserved partition that erroneously has the drive letter
3. Right click the partition and remove the letter, if given the option
   1. If the option to remove the partition is not present, move on to the next section

The manual way

1. Open command prompt as admin
2. Type diskpartand hit enter to start the diskpart program
3. Type list volume and hit enter
4. Find the erroneously mapped drive letter, take note of the volume number for that partition
5. Type select volume # and hit enter
6. Type remove letter=X and hit enter, where X is the drive letter in question
7. Check Disk Management or File Explorer to verify the drive letter mapping is removed