On Vista I had to pause the provider and disable the self-defense module.
Then run Unblocker, unblock ashserv.exe process used by the log.
Then delete the file with Unblocker.
I could not save an edited log with the above procedure, I need to delete the log.
Well, in all honesty, all programs that are running, and holding a log open to report the finding of the program, I'm not surprised that you had to stop the provider first, and gain permissions under Vista by using the Unblocker program to delete the log.
It's like a system file. The A/V program holds it open in order to write any suspicious findings to it when it finds them.
Vista adds another wall by protecting deletion by the user, which seems to be a good thing.
I don't see anything wrong in what the program is doing. It looks like it's doing it's job?