4/24/2009

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 been. That’s good!

In IIS 6.0, getting compression completely enabled is tricky. Tools like ZipEnable from Port 80 can make it a lot easier, and they provide the kind of fine-grained control that lets you disable compression on  a single directory.

Windows 7 Upgrade path from a Beta: No can do?

The RC (Build 7100) versions of Windows 7, which will be available to human beings shortly,  will not upgrade over a pre-release version of the same OS. But, not to worry! The Windows 7 Engineering Blog provides an explanation and instructions on how to do it. They acknowledge that tens of thousands of people at Microsoft alone have been using Windows 7 pre-release builds as their primary OS.

Essentially it is as simple as copying all the files from the burned DVD to a folder on the target machine, then editing the file CVersion.ini in the Sources folder to have a MinClient value lower than the down level build. For example, you would change 7100 to read 7000. Save the file in the same place and run setup from the folder on the  hard drive itself, and you will be allowed to upgrade.  As always, there are a number of cautions and caveats in doing this, so read their blog post carefully. These same steps will be necessary when going from the RC to the RTM milestone.