The scheduled scan execution mechanisms changed completely, I believe,
between beta1 and beta2.
Beta2 uses the Windows scheduled tasks mechanism. There is a command line
portion of Windows Defender--mpcmdrun. You can see the arguments this
executable takes by just running it at a command prompt, and you can, in
fact, effectively create your own custom scheduled jobs--quickscan daily,
fullscan at longer intervals, if you like, for example.
We've seen a number of posts like this and the problem seems to relate to
Windows 2000 systems. Things to check are what credentials the scheduled
task is set to use--are they valid? and, perhaps, trying your own job and
seeing whether you can make that work--perhaps using administrator
credentials. I seem to recall that one thread involved an argument syntax
in the automatically created job which apparently was incorrect. Removing
one of the arguments fixed the problem.
I'm being pretty vague here, and if you aren't familiar with command line
work or the scheduler, this probably won't help you much (and maybe not even
then!)--but that's what I'm remembering at the moment--been on vacation, and
it's hot, and late too!
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