GMail Outgoing Mail Server - SMTP

For some reason I have recently been getting this notification when trying to send out an email from Mac Mail: This message could not be sent. It will remain in your Outbox until it can be sent.

This message could not be sent because your account does not have a preferred outgoing mail server. Select an outgoing mail server from the list below.

When I go to my preferences and accounts I see I have Gmail - Google POP and Gmail Google IMAP. They both have incoming servers listed but on both outgoing servers it is listed as "None." I went to edit SMTP list but I am not sure what to enter after doing so.

I have no idea why this was erased. It has worked fine for years. Any help is greatly appreciated.

Thanks,
Jeff

Use "smtp.gmail.com" for your outgoing POP server. This is for your gmail account and also make sure your password is correct.

I had something similar with just one of 6 gmail accounts. "Bad" account also worked fine with other apps (e.g. Airmail, Mailplane, etc.). Only thing that worked was deleting the account from Mail.app, quitting it, restarting it, adding the account again. Pretty easy and worked.

Preferred Outgoing Server?

I'm getting a similar message when I send emails. "Cannot Send Message" because your account does knothole a preferred outgoing mail server....Select from the list....." I select the correct email server; there is only one to choose. Everything is fine for about 25 emails, then this same message pops up again. Does anyone know how to fix this? Thanks!