I have the same problem that another person has with the following message. "5.7.8 bad username or password (Authentication Failed)"

I basically cannot send email.  I looked at some of the other posts and have done everything you suggested etc and the problem still exists.  This is a critical issue.  I found interesting that you suggested sending you the logs when the problem is that I cannot send anything.  What I did was save them and sent them thru my other email.  You have the logs and I have done everything.  PLEASE HELP ME…DONT IGNORE ME.  btw…my wife has Outlook and uses Verizon…i checked hers and there is not problem…her email is a sub account of mine.  this problem has to do with emclients relationship to verizon.

Hi Ron,
are you using a Verizon account? This issue is unfortunately connected to a Verizon’s authentication issue, please see my statement to this issue here: https://forum.emclient.com/emclient/topics/authentication-failure-on-verizon-net-for-outgoing-mail-h… Verizon is having issues while using CRAM-MD5 authentication, which is a standard for eM Client while using your account and can not be disabled.

Thank you,
Paul.