Number of different ways to go about this ... you can modify IIS to extend the timeout of scripts. However in your case it would probably be better to do it in a "case-by-case" basis.

A number of other users have asked this question ... check out Browser Timeout for your best option ...

Your best bet would be to go with NPH (non parsed headers), you may need to apply a patch to IIS depending on your version. Check this out for more info.

Read up and see if you have "issues" then.

- f o o g o d