On a Web site, I have a situation that I am not sure if this is an optimization in SQL Server or in IIS that need to be done.

While we are optimizing some indexing, sometimes, a user might use an advanced search to perform a very complex search. Such index are not always present as we are fine tuning that. Until then, in some cases, this might result in the IIS hit to go over 5 minutes. So, the user will get an error on that timeout. This means SQL Server was not able to answer the request within the allowed timeframe. However, when this is the case, other users are affected by that and also receive the error. How can I prevent one query like that to bounce on others?