Various reports from the Internet and from our own testing seem to indicate that there is a problem between Internet Explorer 8 and the immunization feature of Spybot - Search & Destroy causing a slow startup of IE 8.

Seeing all those different opinions floating around, we want to clarify what the Immunization feature does. It is one level of our protection that does protect you even if Spybot-S&D is completely shut down. This is possible by using the browsers own lists for blocked sites, by filling them with a huge list of bad sites known to us. And Internet Explorer, starting with version 8, seems to have problems with huge amounts of sites added there.

Critics say that this kind of protection is not that good because recent malware sometimes uses new servers every day even, but then, this is just one layer of our protection. Our Internet Explorer plugin is better able to deal with these, but we feel that's not the point.

Quality assurance is a very important factor of software development, and unoptimized list handling is the probable cause for most performance issues. Whenever software does support lists of data that are not fixed in size, but where the size, like in this case, is open to the user, software tests should include performance tests on huge amounts of data. And usually, it's really just choosing a better algorithm for searches, for example.

Granted, at times a release is pressing and testing gets neglected and not as detailed as it should be - it never is. We know that quite well ourselves: just a few months ago we did slow down IE through our own plugin because we did not expect users to have tens of thousands of cookies at the same time. Did we expect users to cut down on their cookies? No. If you offer a feature, like Microsoft offers to put websites into a Restricted Zone, then please try to support in all ways the users might use it.