Hi Yenelie. This is because the particular file "windcp32.rom" is missing, and your system is trying to load it when you login. I did a google search for the file name, and found no results. This is almost a guaranteed sign that this was some part of a malware infection that has only been partially removed.
Rather than take you through fixing this specific error, I would prefer that you visit our malware removal forum and get a check up to make sure you have no other viruses lurking around. At the same time they will most likely fix this error for you.
If you continue to have further problems with this error after your malware check up, return here and I'll tell you how to fix it.