Has anybody else had this problem?

I transferred a .txt file to my reader(just got it yesterday) and before I could even load it up, the thing just suddenly locked up. No buttons do anything. When I try to power it off it, it doesn't work. When I try to hard reset it, it doesn't work. Something similar happened last night but it managed to snap out of it on its own(it started working again and went through every key I had pressed in order). All I see is the main screen(Books, Audio, Pictures). When I plug it into my computer, the Reader finds it and I can add/remove books. The "Do not disconnect while transferring" message always displays on the screen while it is plugged in. I'm not sure if it was doing that yesterday. Anyway, any advice or help would be much appreciated.

I had a similar problem with a large .rtf file-- it had a bunch of photos. I removed the photos and resaved the file. Deleted it from the reader and then added it again. Worked fine after that. The problem seemed to be both the photos and the overall file size.

The "do not disconnect" message always stays on the screen until you press the eject button in the connect software or close the connect software. It isn't really saying a transfer is in progress, just warning you not to disconnect if you are.

I tried deleting all my files, but none of the keys will respond to anything. I'm gonna let the battery die and then see if it will work after that. If that doesn't work, I might have to return it :(