Hi slacy84.
So that we can best assist you, we will need to gather some more information. Please answer the questions below:
1. The 5.25" x 7.25" is not considered a standard envelope size. Did you create the custom page size of the envelope at the printer?
2. Are you loading the envelopes in the paper cassette tray, or in the manual feed slot?
I look forward to your reply. If you need immediate assistance with this issue, please call us at 1-800-OK-CANON (652-2666), Monday - Friday 10:00 a.m. to 6:30 p.m. ET (excluding holidays).