Ok you can put the battery back in. Ok tell me more about this password XXXXX you said it's the login for windows or is this actually a black screen asking you to enter the password XXXXX want to make sure.
If that program has malfunctioned and it is in fact a hard drive password XXXXX are only two ways to fix it. The first dell my have a program to send you to fix this or the program has severely malfunctioned and the hard drive would need to be replaced and windows would need to be put back onto it. What you would need to do is contact dell and ask them if they have a program for this particular problem or a way around there software if not you would need to replaced the hard drive and have them send you the hard copy of the windows operating system disk and the drivers and applications disk to restore your machine to the way it was purchased. Sadly when these programs malfunction it can cause a mess. I am so very sorry about that but that's how you would need to fix the problem. Please don't leave me negative feedback by the way if you need more information please tell me I am just very sorry that your computer malfunctioned I really am.