Cannot change unallocated space into partition with drive letter

I want to create a new partition inside Windows 21H1 for a new Macrium backup until I can later get a large enough USB stick (in addition: I want both internal and external storage). I did take some unallocated space from C:/ -- cannot have storage destination in C.\ or any other disks being backed up! -- which is more than large enough for this but the only choice Windows offers is the Simple Volume Wizard which does not allow me.

Hello @Airider

Kindly, read this and you'll see that everything's right. You'll need some conversions.

If you're not familiar with command prompt (diskpart), MiniTool Partition Wizard ('Home user' is free) can easily help you enough.

Is the drive a Legacy-MBR or EFI-GPT ?
Windows Disk Manager isn't a good disk manager.
Install MiniTool Partition Wizard

Thank you, that's what I did using the Extend Volume Wizard.


All back as as it was and I will get another SanDisk 64 GB USB stick for external use only.

Attachment 337241



Macrium now


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