What should you do if dir > lpt1 does NOT print a directory list?

I had printing working fine from WINDOWS 7 for a few days, but now I am having trouble with the net use command again. When I manage to get the net use command to complete without an error message (seems to be a random event as to whether it works or not) and I go into my books, it gives me an error message and will not print, saying “cannot write to file specified”. So I think I have lpt1 messed up somehow… any recommendations? (LPT1 is what I have specified as the file name in print options)