Hi godfrey,
Please consider the following guidelines:
• Make sure paper is not stacked higher than the paper guides inside the bypass tray.
• Load envelopes with the print side down, and the open end of the envelope facing out from the printer.
• When printing on envelopes, set the envelope size using the printer driver or control panel.
• Before loading envelopes, remove any air inside and make sure all edges are sharply creased. If envelopes are curled, straighten them before loading.
• Depending on the printing environment, envelopes may be output with the edges wrinkled, with toner marks on the back, or blurred.
• Depending on the type of envelope or printing environment, envelopes might be output creased or printed improperly. In such cases, try changing the loading orientation.