I agree with the previous post. As they mention trimming rules, start with the common ones like CAST(, DECLARE, EXEC to see if you stop injections. If you just monitor the querystring item, that can help cutdown on false positives. I tried monitoring the RAW parameter and had a lot of legitimate traffic blocked. The only way as the other poster said is to validate your input parameters before submitting to your data store.
Steve Schofield
Windows Server MVP - IIS
http://weblogs.asp.net/steveschofield
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