This was my first interview in nearly 10 years, and my first technical interview ever. Prior to the technical interview I was told I could use any language and I chose C#. My interviewer, however, said he wasn't familiar with C# and insisted I choose another language to which I replied that I was told otherwise and I wasn't prepared to use another language. On questions about my career history, the interviewer seemed annoyed that my answers were too long and told me to keep them short. He didn't really seem interested in what I was saying. I was dumbfounded, and stumbled through the rest of the interview like a deer in headlights. I couldn't focus on the technical portion, and obviously blew my chances. I wish I'd have just declined from the very start of the conversation. I could have prepared for another language or requested a different interviewer. I just expected more - and I'm sure they did too.