I have hp photosmart 7850. I was printing envelop and there was paper jam. I pulled out the stock and jammed envelop and ever since the printer would not load paper to prinit and keeps flashing for error. Please help me.

I have had this happen to several people and also to me. What I did is to take a sheet of Card Stock (Heavy Paper) and put it through the feed putting pressure on the Card Stock and pressing on the feed button. What happens is that a piece of the jammed envlope or document gets caught in the feed way and will not allow the document or envelope ( in your case) to pass. It should solve your problem if it works. Bud