I found an article which is nearly correct. Here is my correct solution: Turn off and disable ALL junk filtering 1. Go to account name at upper left, above Inbox and below “+New Message”. 2. Right click on that 3.Go to “Settings” which is the last entry in the drop down menu. 4. Go to “Junk Settings” 5. UNCHECK “Enable adaptive junk mail controls for this account” 6. Go back later and confirm that the box is still uncecked. 7. Go further down to “Junk Settings” in “Local Folders” and do the same thing (usually this is the same screen as before and usually will be unchecked already). The article at https://support.mozilla.org/en-US/questions/1061256#answer-726506 has nearly correct instructions.