A .prn file is a file that has been created using the "Print to file" option in the print dialog of a program, saving the file contents in a format that printers understand, here's how to use it:

How to Print From a PRN File

When you print to a file the program outputs whatever it would have sent to the printer you have attached to your computer to a file instead. The idea is that later you might want to send this file to a similar printer on a different computer. So, the main use for a .PRN file is to copy it to a printer in order to get the output. You can open a .PRN file in any text editor but what you'll likely see is your text surrounded by a whole bunch of "junk" which represents all the various printer codes necessary to set margins, special spacing, graphics, etc.

Printing this file successfully requires a few assumptions:

• The two printers are identical or, at least take the exact same commands to do the exact same things.

• The printer you want to print on is set to be the default printer for the machine it is connected to. If it's not, use the Control Panel to set the printer to be the default.

• The printer is connected to a physical port and not via USB (read on even so; the solution to this is at the end).

For this example, we'll assume that the .PRN file is named OUTPUT.PRN and is located on a floppy disk in the A: drive. Substitute the proper path for whatever filename and drive you are using. Here are the steps...

• Create the .PRN file on the first computer. Open the application, select print, select the proper printer, check the Print to File box, and give the file a name.

• Copy the file to removable media so you can carry it to the second computer (or use a network to transfer the file there in a location you can later find.

• Open a Command Prompt: Start | Programs | Accessories | Command Prompt

• Use the CD command to navigate to the location of the file or know where it is so you can specify a path to it. Recall that in this example we're using A:\OUTPUT.PRN as the file you want to print.

• Issue the following command: COPY A:\OUTPUT.PRN /B PRN
  This command does a binary (/B) copy of OUTPUT.PRN to the device PRN which is the system name for the default printer. A binary copy is used so nothing in the file is changed during the copy process.

Assuming the printers are the same and the output printer is the default device the file should now print. What you've basically done is to tell Windows to copy the output file to the default printer using a binary copy (i.e., don't add any carriage returns or line feeds and ignore all control codes; just passing them through as they are in the file).

If connected via USB...

If your printer is connected via USB then the above command needs to be modified as follows:

• COPY A:\OUTPUT.PRN /B \\Computer_Name\Printer_Share_Name

To get the Computer_Name open the Control Panel and select System. In the dialog that opens select the Computer Name tab. There you will find the name associated with the computer (ignore any periods after the name if there are any). To get the Printer_Share_Name open the Control Panel and select Printers and Faxes. Select the printer you need to print to and then the Share link in the left menu. If the printer has no share name then you will need to assign one.

Shortcut: Instead of the \\Computer_Name you can use \\127.0.0.1 (every computer's local network loopback address) but you still need the printer name information (tested and confirmed on Win2k and Server2003, thanks to Brad M).

Once you have both the Computer_Name and Printer_Share_Name insert these in the command above. Note the double backslash in front of the Computer_Name and the single backslash that is between the two.

Note: If the printer is a network computer then you would substitute \\Print_Server_Name (the name of the print server on the network) for \\Computer_Name in the above.