A printer prints symbols or gibberish when it receives data it can’t read. The usual causes are a corrupted job stuck in the queue, the wrong or a damaged driver, a printer language mismatch, or a faulty cable. Clear the queue first, then answer the questions below to find which one you have.
By Printer Test Page LabLast updated
Most likely
If a page the printer prints on its own is also garbled, the computer is not involved. That points to a fault or setting inside the printer.
Most likely
Pages of code usually mean the computer sent PostScript (or another printer language) to a printer that can’t read it, so it prints the commands as text.
Then reprint: Fine text sheet
Most likely
Wrong letters or symbols in otherwise readable text usually mean the printer used its own built-in font instead of the one in your document.
Then reprint: Fine text sheet
Most likely
Reused, mostly blank sheets can make a new job print over old text, which looks like garbled output.
Most likely
When only one document comes out garbled, the file or the program printing it is usually at fault.
Then reprint: Fine text sheet
Most likely
Epson notes that the first job sent after a computer wakes from sleep can come out garbled.
Most likely
Printing with a generic driver, a driver for a different model, or a damaged one is a common cause of random symbols.
Then reprint: Fine text sheet
Most likely
Text that is garbled in different places on each try points to the cable or connection. A USB cable that is too long can pick up electrical noise.
Most likely
A damaged job in the queue can keep sending garbage to the printer. Clearing it, then fixing the driver if needed, solves most cases.
Then reprint: Fine text sheet
Your computer doesn’t send letters to a printer. It sends a stream of commands in a printer language, most often PCL or PostScript, that tells the printer where to put each mark. If that stream is damaged, cut short, or written in a language the printer doesn’t understand, the printer does its best with what it got. The result is random symbols, odd characters, or page after page of code. Xerox, for example, says gibberish is usually caused by the printer not having the PostScript language installed.[1] So the fix is almost never inside the printer. It is the job in the queue, the driver that builds the stream, the cable that carries it, or the file itself. A quick way to tell: print the printer’s own settings page. If that looks normal, the printer is fine.[2]
| What you see | Likely cause | Fix |
|---|---|---|
| Random symbols on many pages, from any app | A corrupted job in the queue, or a damaged driver | Clear the queue on every computer, restart the printer, then reinstall the driver |
| Lines of code such as @PJL or %!PS | PostScript sent to a printer without PostScript | Use the PCL driver, or the driver for your exact model |
| Garbled in different places each time | Cable noise or a hub in the way | Connect directly with a USB cable of 3 m or less |
| Only one document, often a PDF | The file or its fonts | Print As Image in Adobe, or print a different file to compare |
| Readable text with a few wrong symbols | The printer swapped in its own font | Turn off TrueType font substitution in the driver |
| Only the first job after the computer wakes | A job corrupted during sleep | Print it again |
A damaged job can keep feeding garbage to the printer, and some printers will spit out page after page of it. Brother’s first step is to delete pending jobs on every computer that uses the printer, then turn the printer off for 15 seconds.[3] In Windows 11, the queue’s menu has Cancel all.[4] On a Mac, open Print Center and delete the jobs.[5] If a job refuses to go, clear the print queue with the spooler steps.
Random characters often come from a generic driver, a driver for a different model, or one that has been damaged. Epson suggests checking the product name at the top of the driver window to make sure it matches your printer.[6] Canon lists printing from Windows without its own driver as a cause of unreadable characters.[7] If the name is wrong or the problem keeps coming back, remove the printer, delete the driver and install the current one from the maker’s site.[8][9]
PCL and PostScript are the two common printer languages. Many office lasers understand both, but plenty of home printers understand only one. If you install a PostScript driver for a printer that has no PostScript, the printer prints the commands as text instead of following them. Print the printer’s configuration report to see which languages it has.[1] Xerox’s workaround is to use the PCL driver,[10] and a Microsoft troubleshooting FAQ suggests switching between PostScript and PCL in either direction.[11]
If the garbage lands in different places on each try, suspect the connection. Brother says to remove hubs, extensions and splitters and cable the computer straight to the printer.[12] Canon notes that a long USB cable can pick up electrical noise and recommends one of 3 meters or shorter.[13]
When only one file comes out wrong, print a different document from a different app to confirm the printer is fine.[14] For a PDF, Xerox suggests turning on Print As Image in the Adobe print window’s Advanced settings.[15] If readable text has a few wrong symbols, the printer may be using its own built-in font instead of the document’s. On Canon’s Generic Plus LIPS4 driver, the fix includes turning off TrueType font substitution.[16] And if your text printed over old text, check the paper: reused sheets can look like garbled output.[17]
Print the fine-text sheet from your browser after each fix. It is all ordinary text in sizes from large to tiny, so a driver or font problem shows straight away. If it prints cleanly but your document doesn’t, the problem is in that file or app.
Printed? How did it look?
What to look for: fine text sheet
What to look for: full text page
What to look for: black and white test page
Fine text sheetUS Letter · true size
HP’s support pages did not load for our checks, so HP steps are not listed here. See the HP printer page for its reports.
Fixed? Confirm it
Print a test page from your computer, then the document that failed. If the printer prints its own test page but still won’t print documents normally, see test page prints, documents don’t.
Usually because the printer is receiving data it can’t read: a corrupted job stuck in the queue, the wrong or a damaged driver, a driver for a printer language the printer doesn’t have, or a cable that scrambles the data. Clear the queue first, then check the driver.
Pages that start with commands like @PJL or %!PS mean the computer sent a printer language, usually PostScript, that the printer can’t interpret, so it prints the commands as text. Cancel the job and switch to the PCL driver or the driver for your exact model.
Cancel every job in the queue, or turn the printer off, to stop the pages. Then delete pending jobs on every computer that prints to it, restart the printer, and reinstall the correct driver before printing again.
A single garbled PDF usually means its fonts aren’t being handled correctly. In Adobe Acrobat or Reader, open Print, then Advanced, and turn on Print As Image. That sends the page as a picture instead of text.
Checked 2026-10-13.