Having the same issue with a Studio 1810 since last night. Thought all these questions on here were just popping up because that's what I searched for, didn't realize they were all from today. This is craziness. I assume, like me, a lot of you can't get to setting this stuff up during the week, and were looking forward to getting it all working for some recording on a Saturday. And no support for a silly situation completely out of our control, and probably easily rectifiable if someone was working over the weekend to maintain the serial number validation system. We can't all be mistyping numbers or letters.