defraggler and truecrypt volume encryption

I have a notebook w/C: encrypted by Truecrypt volume encryption. Previously defraggler was able to analyse and defrag. W/ 1.05 and 1.06, the drives squares are grey and both analysis and defrag are reported as "failed".

I have external HDs totally encrypted and defraggler still recognises and operates on the virtual mounted volumes. So not truecrypt per se, but only encrypted boot volume.

Suggestions?