I think my biggest pet peeve right now is production being different from our test environments.

Isn't that usually how it's supposed to be?

@ScribeOfGoD architecturally. Different versions of .net

@ScribeOfGoD In this case, .NET Framework was different.

Prod and QA should run same OS, same underlying tech and connections should be similar (SQL servers on the same versions, and so on). Running .NET Framework 4.6 on Prod, 4.6.1 on QA, I deploy new version with web.config and BOOM, IIS shoved the app into an eternal redirect.... Event viewer had logs, but not app logs. UGG.