Can't print from the MP tray?

nothing im afraid mfps crinkle copiers all you can do is try to reduce the wrinkle try putting the flap inside the envelop sorry but other than that's theres not much your can do

sorry buddy but mfps wrinkle envelopes he have tried many things on many models they all wrinkle the best thing you can do is try to reduce the wrinkle we tuck the flap inside and that helps a little other than that sorry

The printer trays accommodate most sizes and types of paper, transparencies, or other
specialty media. Follow these guidelines when loading paper and media in the trays:
- Envelopes, labels, and glossy paper can be printed from Tray 1 (MPT) only.
- Transparencies and custom size paper can be printed from Tray 1 (MPT) and Tray 2.
- Fan paper, transparencies, and labels prior to loading them in the tray.
- Use only paper envelopes. All envelopes should be printed single-sided only. Some
wrinkling and embossing may occur when printing envelopes.
- Do not overload the paper trays.
- Adjust the paper guides to fit the paper size.
- If excessive jams occur, use paper or other media from a new package.

which tray is paper in? the MP tray is the manual bypass tray in front of machine. sounds like your software is setup to utilize the MP tray for the labels, which is the best thing to do.

hth
razors

Tray 1 (MP Tray) paper size and paper type needs to be set to either envelope or labels.

"MP tray" refers to the manual paper tray. This is the common setting for most word processors whenever printing media other than paper. This message will come not only for labels, but for transparencies, card stock, envelopes, etc. The reason for this is that the manual paper tray is designed to provide a straighter paper path that helps preventing your labels from peeling inside the unit. Therefore, I do not recommend placing them in the regular paper tray. Take note that you should also check that the labels purchased specify they are meant for laser printer or copier. Regular labels, or labels designed for inkjet printers will surely come off inside your printer and cause damage that the warranty will not cover.

Be blessed.

MP LOAD,
PC LOAD, or
LC LOAD
paper size,or
envelope size
The printer received a request for a paper or
envelope size not available in the printer.
MP LOAD: Load MP Tray with the requested
media. If the size is not selected in the printer
control panel, use the [MP[Paper[Size] key to enter
the requested size, or press [Shift] + [Continue] to
draw the requested size from another source, if
available.
Note: If MP LOAD remains in the display, you may
have to clear the buffer by resetting the printer.
Press [Shift] + [Reset].

On an MP-C4500, envelopes must be printed using the bypass tray (the fold-out tray on the right hand side). Put the envelope in face-down and tighten the two fences so the envelope is snug.

When printing the envelope, make sure the print driver is set for the correct envelope size. If envelopes tend to jam in the printer, try setting the bypass paper type for thick paper.

is this still a current issue?

I have called canon with this problem more than once and they keep telling me that I am using a "paper" that is not supported. I finally gave up and ended up telling them that I am now going to use my cheap HP printer because it can do what it's suppose to.