Windows 7 No Longer Likes 2000 / Log On Error

I have a windows 7 computer and a windows 2000 on a wired network. The windows 7 and 2000 previously played nicely although it was a bit of a pain to get it to work the first time, don't really remember what the issue was. I have a big old CAD plotter connected to a parallel port on the windows 2000 computer and previously was able to use it from the windows 7 computer. I was also able to access any file on the windows 2000 from windows 7, it all worked fine a few months ago. I haven't had the win 2000 computer on for a while but recently needed to use the plotter. I now get a log-on error when trying to access the win 2000 from the win 7, but it shows up on networks. The log-on error window shows a domain with the name of the windows 7 computer listed as the domain name, but nothing is set to be on a domain. I can access the files on the windows 7 computer from the win 2000 computer with no issues in that direction. There is no home group set up (think that was the issue the first time) Windows 7 is always updating itself and I suspect that's part of the problem, I am guessing something went back to a default during an up-date but I can't find it.