HP 21 — Page too complex

What this error means

The page contains more data than the printer can process at speed — dense graphics, huge images, or too little printer memory.

Symptoms

• Error on graphics-heavy pages only
• Partial pages printing

Try this first (safe DIY steps)

1. Reprint — the printer often recovers with its 'press OK to continue' path at reduced quality
2. In the driver, lower print resolution or enable 'print as image' for the problem document
3. Flatten/re-export the source PDF

Safety: power off before any physical intervention. Never bypass covers or interlocks — fuser areas run hot enough to burn.

When to call a technician

Not a service issue; if constant, the printer may simply be underpowered for your documents.