If you have not changed your partitioning scheme since you unencrypted the
drive it is probalby just a matter of no contiguous disk space. I ran into
the same thing. To solve it I defragmented the drive (righ-click the drive,
select properties, click tools) and deleted a few files I did not need any
more. BitLocker hogs a lot of disk space when it first encrypts, and it does
not seem very elegant about selecting it across randomly spaced free space.

How come you decrypted the drive anyway?

"David N" wrote:

Sorry I forgot to mention that the error it gives is that there is
insufficient disk space for bitlocker to encrypt the drive, however I have
over half of my hard drive free and my disks are partitioned correctly.

"David N" wrote:

I decrypted my hard drive after encrypting it with bitlocker, however now I
can’t seem to encrypt my hard drive with Bitlocker again.