I have Microsoft Office 2016 and I am using Outlook to connect to AOL (verizon.net) email. I have a lot of folders and email I want to keep. Recently, Outlook stopped RECEIVING email and nothing I've tried seems to fix it. (FYI, I obtained MS Office Professional 2016) from a prior job, and reinstalling it prompted for the key, I don't have it).
So I have downloaded 4 windows email clients (eM, Mailspring, Thundermail, Opera), all fail to download email contained in "custom" folders defined in AOL.