Continous "paper jam"...

Question

I got a Pixma 530 all-in-one approx. 2 months ago; I tried printing a #10 envelope the other nite using the front(bottom) paper tray. It printed fine but there after I keep getting a paper jam message. I've checked all visible areas but have found no bits of paper nor were there any tears in the envelope yet the message persists. Can anyone help.Baiz