Printer prints one line of gibberish ("%PDF-1.4") then nothing

The printer printed a single line of garbage at the top of the page — sometimes literally %PDF-1.4 — and then spat the page out blank. Every job did the same thing. The document was fine; the printer was raw-dumping the start of the print stream as text.

Root cause

The CUPS queue had fallen back to a “Local Raw Printer” with no driver/PPD. A raw queue passes the job straight to the printer with no rasterization, so the printer receives a PDF/PostScript byte stream it can’t interpret and prints the first line literally — the %PDF-1.4 magic header — before giving up.

This commonly happens after a “No space left on device” (ENOSPC) event, even a transient one on a disk with plenty of free space: CUPS fails to write the generated PPD during setup and silently leaves the queue raw. A symptom of that is /etc/cups/ppd being empty.

The fix

Delete the driverless queue and recreate it with the IPP Everywhere / driverless model, which makes CUPS do the rasterization:

lpadmin -x BrokenQueueName
lpadmin -p BrokenQueueName -E -v "ipp://printer.local/ipp/print" -m everywhere

If you don’t know the device URI, list what CUPS can see:

lpinfo -v

Pick the matching usb://… or ipp://…/dnssd://… line and use it as the -v value. Print a test page — it renders correctly.

Why -m everywhere

everywhere tells CUPS to auto-generate a proper driver from the printer’s IPP attributes instead of leaving it raw. It’s the modern, vendor-driver-free path and the cleanest way to rebuild a queue that lost its driver. If you have several duplicate/garbage queues, delete them all with lpadmin -x and rebuild the one you want — don’t try to repair a raw queue in place.