I spent two weeks writing a WordPress plugin to take some form data, process it through another website, and take the result to Salesforce. the client had a "Salesforce specialist" doing everything on the Salesforce side and refused to give me access to see if the data was properly pushed through.

Finally I got it in working condition when suddenly it stopped working, I hadn't changed anything since it worked so I asked if he could have possibly changed something. We argued for over 4 hours about who changed something, the whole time I was looking for the error in my code. At 6pm I finally told him I would need to take a look at it tomorrow.

Overnight he sent me an email:
"Hey, sorry about the confusion yesterday, I set Salesforce to deny duplicate email entries, looks like once I removed that everything is working."