Lexmark C2335
Step 1
Use an envelope that has been stored in a dry environment.
Note: Printing on envelopes with high moisture content can seal the flaps.
Send the print job.
Does the envelope seal when printing?
Go to step 2.
The problem is solved.
Step 2
Make sure that paper type is set to Envelope.
From the home screen, touch Settings > Paper > Tray Configuration > Paper Size/Type.
Contact customer support.
Here are troubleshooting steps for the unusual grinding, rubbing, or rattling noise when printing using Lexmark CX/CSXxx, XC/Cxxxx, MC/Cxxxx, and C9xx.
Watermarks are not appearing when printing from Google Chrome and Microsoft Edge