Authentication section appears under Accounts/IMAP on one of my computers, but not on the other. Why wouldn’t they both show the “Authentication” section of the choices. All other settings seem to be the same.
Hello David, can you please make a screenshot of the issue and submit it to us here on the forum?
What mail service are you using with eM Client? And what version of eM Client are you currently using on both of your computers, can you please check the exact release number in Help > About?
I’m using Gmail on both HP Notebooks and eMClient 6.0.22298.0 on 2-TB HP and 6.0.22313.0 on 1-TB HP. 
Hello again David, this is because one of your applications is using a newer release of the application. We’ve adopted the OAuth authentication option for Google accounts in the latest release as Google has decided to shutdown support for regular password authentication with the server. From now on you have to authenticate using a browser window that redirects to your mail server and reaches out for a token that will be stored and used for authenticating with your mail server.
Update your other instance of eM Client to avoid future authentication issues with Gmail.
Hope this helps.
I’ve done the update as you suggest, but am still getting the authentication messages. If some additional action is required, I’m unclear as to what it is. Can you detail further actions that are needed to eliminate the authentication error messages (that are quite annoying? Thanks.
What kind of authentication messages, can you make a screenshot of the issue?
All you should need to do to authenticate with your Google account is to enter your password to the authentication window and confirm, second step requires you to enable access for the listed items, to do so just hit “Allow” below the listed items and the account authentication should be finished.
Is this the verify prompt that never tells who it is from?
Hello Malcolm, not quite sure what you’re referring to, can you please specify your question?
Thank you,