HP Color LaserJet 4500 Printer series - Manual (Page 149)

EN Chapter 9 149
Output is curled or wrinkled
Cause Solution
Media does not meet the specifications for this
printer. Only use media that meets the media-use
specifications for this printer (see the
supported media weights and sizes section in
chapter 3).
Media is damaged or in poor condition. Remove media from the input tray and load
media that is in good condition.
Printer is operating in an excessively humid
environment. Verify that the printing environment is within
humidity specifications.
You are printing large, solid-filled areas. Large, solid-filled areas can cause excessive
curl. Try using a different pattern.
Media used was not stored correctly and may
have absorbed moisture. Remove media and replace it with media from
a fresh, unopened package.
Media has poorly cut edges. Remove media, flex it, rotate it 180 degrees or
turn it over, and then reload it into the input
tray. If the problem persists, replace the media.