IIS 6.0, Compression, and Classic ASP Pages
The incompetent with nothing to do can still make a mess of it. - Laurence J. Peter Well this one is a hoot. Enabled HTTP compression in IIS 6.0, and suddenly Classic ASP pages (yes, we still have a few) that required Integrated Authentication just wouldn’t work. With Anonymous Authentication unchecked, and Integrated checked, and ACL’s on the folder permitting only Adminstrators, you would get a Windows Login prompt as expected but when you would provide credentials, it never went through. As luck would have it, we duplicated the pages on another site where compression was turned off, and those worked fine. On a hunch, I disabled compression on the includes folder, and that fixed it! Seems for some reason that Classic ASP include files don’t like HTTP compression at all. And a thanks to Rick Strahl for reminding me that you need HTTP KeepAlives turned on to use Windows Auth with classic ASP. Compression will reduce our bandwidth to around 25% of what it has be...