I'm guessing that your new computer is running Win XP?
First, share your printer. Click start, got to settings then click on printers and faxes.
Find your HP-4050 and right click on it. Go down and left click on properties. Click on the sharing tab.
Click on Share this printer. In the box that says Share Name: give it an easy name like HP4050.
Now find your computers name. Right click on my computer. Left Click on Properites. Left click on the computer name tab. It will say Full Computer Name.
Click Start, Left click on Run. In the box, type in the word command. This should open a DOS box.
At the DOS prompt type:
net use LPT1: \\computername\HP4050 then hit the Enter
key. Remember to put in your computers name where I have computername. If you typed this in correctly, the computer will respond with: The command completed successfully. You have told your computer to grab everything addressed to LPT1 and send it to the shared printer named HP4050.
If you restart your computer you'll have to re-enter the net use command. Or you could put the net use command into a short batch file that runs each time you restart your computer.
Hope this helps.