Printing envelopes using the document feeder

[JClerk]

I recently purchased a HP OfficeJet Pro8035e because the HP rep I spoke with told me I could use the upper document feeder for envelopes and when I needed to print one, just choose the feeder rather than the tray.  It's because I pay a lot of invoices and print a lot of envelopes and it's too time consuming to always take the paper out of the tray, add envelopes, print and put the paper back in.  The rep said it was possible, but I can't find out how to do it.  Help!

[Valsimot]

The upper feeder on OJ Pro 8035e is used to load originals for copying or scanning, you cant print on something you loaded in top feeder.

For printing you can only use lower tray.