System Info: Windows ME 4.903000 E machine Etower 600is

When I try to do a defrag I get this message:

Windows cannot defragment this drive now because it has been locked by a disk utility. Quit any utilities that may have locked this drive, and then try defragmenting the drive again. ID No. DEFRAG00105

Mosy recently installed program was AdAware SE Personal which I removed but I am still unable to defrag.
Any help would be greatly appreciated.
Thanks