Whew. It has been a crazy two weeks on this project, and it all culminated with a nasty error where Response.Redirect was on the fritz. This one tore me up before I was able to figure out what was going wrong.
Basically I was doing a Response.Redirect on a page, and in Dev and Test it worked like a charm. Even after I moved it to production it worked for a while. But then the horror occurred. The response redirect suddenly would simply post back to the same page - no redirect at all.
I was able to narrow it down to the response.redirect fairly quickly, but I assumed it wasn't playing nice with some server setting in Prod that wasn't switched on in Dev or Test.
Well - I am not entirely convinced that some switch in IIS didn't get flipped, but quite frankly going down that rabbit hole wasn't getting me anywhere, and the client was waiting.
So I looked at all the opages to see how this one differed. Turns out this page was the only one with SmartNavigation turned on. So I set SmartNavigation to false, and voila.
Hope this tip helps some frustrated soul out!
EDIT: I have learned more about this error. See
here for details.