HP Printer Error Code 28 — What It Means & How to Fix It

What Does This Error Mean?

Error 28 means your HP printer ran out of memory while trying to process a print job. The document you sent was too complex for the printer's memory to handle all at once. This is common with large documents, high-resolution images, or multiple complex pages sent together.

Affected Models

HP LaserJet 4
HP LaserJet 4L
HP LaserJet 4P
HP LaserJet 5
HP LaserJet 5L
HP LaserJet 6L

Common Causes

The print job contains large, high-resolution images that exceed the printer's memory capacity
You are printing a very long document with complex formatting on multiple pages
Multiple computers or users are sending jobs to the printer simultaneously
The printer's memory is too small and has not been upgraded for modern document complexity
The document contains many different fonts or complex vector graphics that use extra memory to process

How to Fix It

Cancel the current print job. Press Cancel on the printer's control panel to clear the job from the print queue.

Also clear the queue on your computer — open the printer in Control Panel > Devices and Printers and cancel any pending jobs.
Restart the printer. Turn it off, wait 30 seconds, and turn it back on. This clears all data from the printer's memory.

After a restart, the printer's memory is completely empty and ready for a new print job.
Simplify the print job. In the printer settings on your computer, reduce the image quality/resolution setting from 1200 dpi to 600 dpi or lower.

Lower resolution settings require far less memory. The quality difference is barely noticeable for most documents.
If printing a long document, try splitting it into smaller chunks and printing 20 to 30 pages at a time rather than all at once.

Smaller jobs require less memory at once and are more reliably handled by older printers with limited RAM.
For compatible older HP LaserJet models, add more RAM. HP LaserJet printers from the 4 and 5 series accept standard SIMM memory modules that can dramatically increase capacity.

Check your printer's manual or HP's website for compatible memory part numbers. Adding memory permanently solves error 28 for most users.

When to Call a Professional

Error 28 is a memory limitation issue and does not indicate a broken printer. For ongoing issues with complex documents, a technician can install additional memory modules in older LaserJet models. HP authorized service centers can source and install compatible memory for most LaserJet series.

Frequently Asked Questions

How much memory does my HP LaserJet printer have?

Memory varies by model. Early LaserJet 4 models came with as little as 2 MB of RAM. More modern LaserJet Pro models typically have 256 MB to 512 MB built-in. Check your printer's manual or the configuration page (printed from the printer's menu) for the exact RAM amount.

Will reducing print resolution visibly affect the quality?

For text documents, reducing from 1200 dpi to 600 dpi is virtually undetectable. For photographs or fine artwork, you may notice a slight reduction in sharpness at very close inspection. For standard office documents like letters, invoices, and reports, 600 dpi looks excellent.

Can I add more memory to my HP printer myself?

Yes, on older LaserJet models that support memory expansion. You remove a panel on the side of the printer, locate the memory slots, and insert compatible SIMM modules. HP's support website lists compatible memory for each model. Modern InkJet printers generally do not have upgradeable memory.