I have been in contact with Epson on this issue on my V600. Their latest fix i received today was to run a small utility to remove the Epson driver and clear registry entries. They then have you delete temp files, etc and reinstall. While the fix only partly works, it is better than before. It does not lock up anymore. If you minimize the window it will go down to a small bar of some type that can't be brought back up. but you can close it without killing the process. So my rule is now to not minimize it!!
I am sure Epson will send anyone the utility and instructions if needed. I did install the V600 driver off of the European Epson website (I am in the US). It seems to have a small update which seemed to eliminate the freezing.
Here is the utility and instructions I got From Epson.
Alas I laughed too soon! I really thought this fix was working, and a few times it was. But no more. Like others on this thread, I'm stuck with an expensive scanner that's now useless.
Thanks Epson.
Thanks Microsoft.