Some details would be great as well.
From your post, I would assume you are using the net use command to redirect a local printer port (LPT1) to a networked printer (\\print_server\printer). I would also assume that when you issue the "NET USE LPT1: \\print_server\printer" you receive a message indicating that the command worked.
Are you using any other options with the NET USE -- /PERSISTENT, user and/or password, etc?
If you type "NET USE" in a command window and press enter is the redirected printer listed, and if so what is the status.
Most importantly, can you print a test page to the network printer throught the normal windows process?