I have been having this problem at work. The company I work for said that I was sending reports through with the wrong dates on them. Now I'm not perfect, but I'm pretty good at checking the date. I'll park my cursor there and wait until the doctor says the date and then I'll type it in. Last week, I was fined 10 dollars by my company for putting the wrong dates on 5 reports. The funny thing is though, the dates were correct on my end. The files that my computer keeps had all the correct dates on them. No mistakes at all. I send an email to my boss explaining that I didn't think that I had made these mistakes, but she dismissed it. Then today I got an email again saying that I had messed up a date. My husband was here and is very techy and we started discussing it. He said that I could send them my file and a log/record from my computer to prove that I had not modified the file and I could prove I hadn't messed up. So I sent another email explaining this, this time to the boss of my boss (who was the one who emailed me this time). A few minutes later, someone called me and said they had a "glitch" and they'd pay me back my 10 bucks. Yay! It's not the 10 bucks so much as being believed. You know? Well, that and all the future 10 bucks. It could have gotten expensive.
Also while we were looking at this, I got a call and I won a 25 dollar gift card at the 4H fair yesterday. Cool!