Partition changed from "primary" to OEM; how to reverse it / access data?

Question

Hi!

My external backup HDD (About 1.5TB) has tree partitions. One of them now turns up as an OEM-partition. This happened after I restarted my laptop with boot from USB as the first option. I had this setting from reinstalling windows 10 from USB, and forgot to change it back. There was an error while booting up, but I didn't record it. What's now an OEM-partition, used to be my main backup!

I have not found any way of accessing the data, or changing back this partition to "Primary".

Anyone have any idea?

With Regards,

ACT of Norway

Answer 1

Hello

Here are some steps you can take to access the data and change the partition back to “Primary”.

 

Accessing the Data:

 

You can use a tool like AOMEI Partition Assistant. After installing and running it, right-click the hidden partition and select “Advanced” > “Unhide Partition”. Then, click “OK” to unhide the partition.

 

Alternatively, you can use the built-in command line tool called Diskpart. Open the Run prompt, type diskpart, and hit Enter. Type list disk to list the disks. Select the disk you want to manage, then type select disk z and hit Enter (replace z with your disk number). Enter list partition and hit Enter to display all the volumes. Type select partition x and hit Enter (replace x with your partition number).

 

Changing Back to “Primary”:

 

If you don’t care about the data on the logical partition, you can use Disk Management. Enter Disk Management, right-click the logical partition, and choose Delete Volume. You’ll be prompted that all data on this partition will be erased, click Yes to continue. Right-click the extended partition and choose Delete Partition. Click Yes and space will be labeled as Unallocated. Right-click the Unallocated space and follow the wizard to create a primary partition.

 

If you want to avoid data loss, you can use AOMEI Partition Assistant. Right-click the logical partition you want to convert and select “Advanced” > “Convert to Primary”. In the pop-up window, click “OK” to continue.

 

Please remember to back up your data before making any changes to your partitions.