Using Spybot 1.5.1.13 (and at least one earlier beta-test release), I have been encountering repeated immunization problems.

For example: Yesterday, I updated Spybot, and started the immunization process. After a while, the process stopped, and I could not close Spybot from within Spybot.

I used the Windows (XP Home, SP2) Task Manager to close the process, and restarted Spybot; the same problem arose, so I repeated the steps to close and restart.

After perhaps two or three attempts to immunize, Spybot did increased the number of immunized entries before it once again gave up. It took me some five or more tries to finally get everything done.

There were quite a few unimmunized entries, as I had recently removed and reinstalled Firefox 2.0.0.5, but the places where Spybot stopped, according to the immunization screen, were before it got to the Firefox entries. In fact, the part of immunizing the Firefox entries went rather quickly--again, according to what I could see on the Spybot screen, as I have no way of knowing what Spybot was actually doing.

This is not the first time that I've had problems with the immunization process of the Spybot beta-tests; the previous times were much the same as yesterday, although not so serious in terms of how many times I had to kill Spybot and restart the immunization process.