Cannot enable BitLocker: "Insufficient disk space..."

I had BitLocker enabled, had to decrypt and clear the TPM key becuase I
forgot the password. I now re-enabled the TPM key, initialized it and now
have a password I could get amnesia and not forget.

When I follow the instructions to enable BitLocker again and I follow the
bouncing ball, get to the "Encrypt the volume", C:\ prompt...then I get
informed that I am suffering from "Insufficient disk space for BitLocker...".
I have plenty of free disk space on the volumes selected.

Disk Info:
C:\ - system, 30GB volume with ~19GB free
D:\ - BitLocker 1.5GB volume with 1.4GB free
E:\ - Data 61GB volume with ~40GB free

I have seen other "similar" questions in the Community and they note that
contiguous file space could be the issue, I have defrgged and get the same
result.