Thank you, but my problem extended to the fact that when I went to Preferences/Send forms, the same error message would come up as when I tried to email an invoice. Then it would shut the whole program down. I did finally, 10 hours later, fix the problem. I reloaded Quickbooks but it wasn't until I reloaded Office 2013 / Outlook that it finally worked. I had done this several times before so I have no idea what made it work this time, but I am happy. Thank you for your suggestion.