'Print to file' function in Windows
Before virtual PDF printer was common function in Windows and Windows applications, the only way to produce a "print" file was by using a special "Print to file" option (usually a check box) available in every decent program that exported the file, typically document, as a .prn file.
This function was useful when there was no physical printer connected to the computer and you needed to print your document on another computer that was connected to a printer. The catch was that the same printer driver had to be used on both computers, because otherwise it would not work properly.
Several versions of .prn files existed, some in HPs PCL language and some in PostScript, largely depending on which printer drivers were installed in the computer, but eventually a generic version was used that was more or less device independent.
Then virtual PDF printers started to be common, and the "print to file" function fell into obscurity and the younger generation of computer users no longer uses it, or even knows it still exists even in Windows 10.
Sometimes users find their old .prn files and wonder how these can be printed on modern computers, because prn file type is not associated in Windows and no default application in Windows can open it.
Printing old .prn file on paper
You can most likely find several solutions and guides how to print prn files, but we will show you only the most convenient one.
Use PrnPrint to print .prn files
For this you will need a small and free utility called PrnPrint that can be be used to print any .prn file on paper using your physical printer.
It is a quite straightforward process to be honest and there is no reason for some extensive tutorial. Just load the file and print it.
Typical use of PrnPrint. Notice that although the program offers the default Microsoft Print to PDF printer, you have to pick a physical printer instead.
Conversion of .prn files to PDF
Unfortunately, PrnPrint app does not support printing to PDF so your only option is to print it on paper.
Generally, it is not that easy to achieve prn to pdf conversion and even when you find some kind of solution from various "how to" websites on the Internet, they quite often do not work properly.
Here is a small list of some viable alternatives for a prn to pdf conversion that should work most of the time, but sometimes might not.
Use Ghostscript
Some .prn files may be converted to PDF using Ghostscript interpreter, or some kind of Ghostscript based GUIs for example GhostView. But using Ghostscript requires some moderate knowledge about printer interpreters and it can be pretty challenging for the common user. On top of that, some versions of .prn files cannot be processed properly.
Use some PRN to PDF converter
Many apps and dedicated PDF converters claim that they can convert .prn files to .pdf, unfortunately this is not always the case and a lot of them list prn to pdf conversion just for SEO purposes, i.e. to appear high in Google Search.
Print PRN on Paper and scan it back
You can always try to simply print the .prn files and scan them back to electronic format using your scanner and generate a new PDF from it. This may be enough for sharing, but if you need the text you will have to use some OCR solution, such as OmniPage.