Windows 10: Drive letters/numbers keep changing

Just like I thought, it's UEFI system and two identical drives are confusing heck out of BIOS. I would first make sure that drive (now shown as C*Smile to be in first SATA port and BIOS to point at it as default BOOT drive. If your BIOS is standard one it should show Windows boot manager and exact disk it's on.
Here is on mine:

 

Thanks, I'll give that a try. *Smile

Edit: done as you suggested, all is well at the moment. Will monitor it. Thanks again.

 

Well, it's done it again - after another reboot the drive numbers/letters have swapped over ...........

Any other ideas please how to stop this happening?

 

It must have booted from wrong disk. Give windows partitions distinctive names.

 

It's definitely booted to the correct drive. I'll rename the drives as you suggest but I guess that's not going to stop it getting confused on boot?

 

Lol, no but will unconfuse you !

 

It will only unconfuse me until I clone the drive or reboot the PC again. *Smile

 

Have you tried to rename drives ? Trre's no way to have 2 C: drives or any drives/ partitions with same letter.

 

I've renamed them in My Computer, or did you mean elsewhere?

 

Yeah, there.

 

Ah yes, but when I clone the drive again that will also be cloned ........... *Smile

 

Yes it will but for one instance you will know which one is which. As pointed out, there are other ways to keep ready backup without those pitfalls. RAID array for instance: RAID - Wikipedia where data is written to at least two disks at once.

 

Thanks, I'll look into that.

 

Mike, won't Partition Wizard change the disk signature?

 

Yeah, it would give it another serial number but that would also be cloned and BIOS has no idea about it so it can still be confused. Even every simple format changes serial number.