Interesting.
Just guessing, maybe the scheduled task for Ad-aware is using Smartscan? Smartscan AFAIK will only scan the new items or items that has changes from your previous scan.
On a separate topic, I registered (yesterday) at http://www.lavasoftsupport.com/ and am not allowed to post (yet). If anyone is involved with that forum, can you find out why 'haroldo' can't post.
Try to go here for Resend Validation Email request which might help.

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