How to make a drive with: system in Windows 10?

Question

Windows

Now there are two Windows 10 systems on drives C and D (two partitions on one HDD). The main one, it is also the system one, it is also the active partition D. But the computer is loaded by default from C, as I need. How to make partition C become the main, system and active one, because D is going to be deleted and attached to C using EaseUS Partition Master?

Answer 1

I would do so. Since drive letters can be assigned quite arbitrarily in Windows, I would open Disk Management and assign C to the partition that I am going to make active. Then it would start from an external OS (for example, from any LiveCD/LiveUSB recovery tool), launch any partition manager in it (Acronis DD, Paragon XDM, etc.) and use it to set the active partition to the one with before changing the letter. By the way, since the partition manager is running, you can immediately delete unnecessary partitions and merge them (it is not at all necessary to limit yourself to the EaseUS Partition Master program for this work). Then restart, and the launch will happen from it.
If Winda, after the restart, disposed of in her own way and again changed the letters to the partitions, she would open Disk Management again and restore C on the desired partition.