I have the same problem as in an earlier posting. My junk filter worked fine for many moons, but stopped working last Fall when I switched to an Intel Mac. Nothing I do will get it to start. I have tried resetting and retraining more than once, but the retraining does not work: NOTHING is ever auto-detected as junk by the program.
Moreover, the rules in general simply do not work: if, as someone suggested, you set the rules to capture, for instance, a subject line = "elephant" and run a test with a message containing "elephant" in the subject line, that does not function. I have uninstalled the only Mail plug-in (Act-on), and have tried reseting the junk mail, to no avail. Otherwise, Mail operates normally.
I am using an Intel Mac (which may be telling? the problem started about the time of the switch to this machine), Mail version 2.1.1, Mac OS 10.4.9.
Help greatly appreciated.

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