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12-19-2013 06:18 AM
At the moment the HP Officejet 8600 Pro only allows all envelope printing by:
1-Removing paper tray
2-Removing paper in tray
3-set envelopes in center of tray touching back end of tray.
4-Changing the guides to hold paper in place.
It's a bloody pain, but it works.
12-19-2013 06:59 PM
No, it doesn't work.
I just purchases an Officejet Pro 8600 also, and although I load the tray with a few #10 envelopes, it will not print on my Mac using Endicia for Mac. I continue to get the error message "paper mismatch."
Can someone advise?
12-19-2013 09:23 PM
Suggestion: Under System Preferences for you Mac, select Printer. Then set "Default paper size" to Envelope #10. This is a nuisance, since once you print your envelopes, you will want to seet it back to US Letter.
12-26-2013 05:48 PM
Worked perfectly! This is the first time I have ever attempted to print an envelope, and it was so easy. Thanks a million. Definitely worth several "kudos."
01-20-2014 11:35 AM
I recently purchased a HP Officejet Pro 8600 and I cannot get to print envelopes. I inserted a #10 envelope in the feed tray just like the example on the tray shows and adjusted the side rails and I keep getting an error message saying the paper is the wrong size. What's going on and can you help.
01-27-2014 08:56 PM
YOU CAN PRINT A SINGLE ENVELOPE ON AN 8600! Leave the Paper in the tray, place the envelope (face down with the flap on LEFT) Center the envelope with the rear knotch in the cassette (on top of the existing paper). Carefully push the paper cassette back in. I'm using Envelope Print In Word... Works like a Champ. When I saw the paper setup I expected you'd/I have to Unload the paper to print one stinkin envelope.
03-12-2014 08:58 PM - edited 03-12-2014 09:01 PM
This solution works with OpenOffice Writer without making any changes to anything...
1. Pull tray and remove one sheet of paper (used in step 3)
2. Place an envelope face down against rear and right edges of tray (with "top" of envelope against right edge).
3. Place previously removed sheet under envelope's flap & close tray.
4. Print the entire document (or just the envelope)... [envelopes are always the first "page" in an OpenOffice Writer document]
The printer will pull both the envelope and the single sheet through at the same time. The purpose of the sheet is to act as a "carrier" for the envelope which will pass through skewed if not guided by the sheet.
I didn't read through all the posts in this thread, so sorry if this has been previously suggested.
 available free from http://openoffice.org