Drive in question was my "data drive" and contained:
- BitLocker encrypted partition (created with Win 10, doesn't contain OS)
I deleted the Ubuntu partitions. What remained was an EFI partition. I deleted this using
diskpart on Windows. On Windows disk management the drive was like this:
After deleting the EFI partition the whole disk now shows "Unallocated". I'm sure I didn't delete the Bitlocker partition.
What happened? How can I get the Bitlocker partition back online?
By using Minitool Partition Wizard I found the lost EFI partition. I didn't restore it as I fear data loss.
Testdisk analyze says
Bad GPT partition, invalid signature. Trying alternate GPT Bad GPT partition, invalid signature.