In the past few weeks, I have had multiple people email me that my blog was no longer working. The behavior described is that the browser would hang forever on the page. I believed them, but could not reproduce the problem. No matter which system I typed in the URL from, it worked. Quite puzzling.

The mystery continued until today, when I got multiple such emails and I finally decided I have to do something about it. Through the process of elimination, I was able to figure out that the problem occurred only when a link from another web page is used to access the blog (or from a bookmark). I was never seeing the problem because my test case was to type in the URL. Having figured out when the problem occurs, the general reason for the problem was obvious, but not a specific one. Since the problem only occurred through a link, it pointed to a referral tracking/logging issue.

Digging around, I chanced upon this post in Scott Hanselman’s blog. The problem occurs if DasBlog’s “Movable Type Blacklist” setting is enabled. Turns out that not very long ago, Jay Allen, who maintains the MT Blacklist that DasBlog refers to at startup, has started banning IP addresses, but returns a valid HTML document with comments instead of an HTTP 302. This causes issues with DasBlog’s referral logic and prevents the page from loading.

Glad I got this one figured out…it was driving me nuts.