Solved Delete Win 10 partition in dual boot with Win 7

[Jemawi]

My problem is that I have made a dual boot system with Win 7 on Partition “C”, and Win 10 preview on Partition “D”. I no longer want the Win 10 preview and want to uninstall it. To do this, I have done as follows:
1. Boot to Windows 7. Make sure you are using an Administrator account.
2. Click Start and type msconfig In the results click msconfig.exe. In the Configuration editor, click the Boot tab. Make sure the Windows 7 is set as the Default OS. If it is not the Default, select Windows 7 and click the Set as default button.
3. Click the Windows Technical Preview entry and select the Delete button. Exit msconfig.
4. Click Start and type Computer Management, In the results click Computer Management. On the left side menu, click Disk Management.
5. Locate the hard drive partition where the Windows Technical Preview is installed. Right click that partition and select the Delete Volume option. Confirm the deletion.

This is where the problem starts: When I try to delete the “D” partition, I get the following warning:

“The volume WIN 10 (D) Simple Volume is currently in use. To force the format of this volume, click Yes.
Warning: Forcing a format might cause unexpected errors in the application that is using this volume. Do you want to continue?”


Is it safe to delete (reformat) the partition with Win 10?

 

[AddRAM]

Post a shot from Disk management first, before you proceed.

 

[Jemawi]

Please find attached a picture of my disk management.

 

[AddRAM]

It`s totally safe to delete D.

C has the system files and it`s marked Active, you`re good to go.

 

[Jemawi]

Thanks a lot, AddRAM. Win 10 is gone, and Win 7 boots up like a rocket!

 

[AddRAM]