I solved it by checking the settings and resetting a couple of them according to an article - and magically everything is fine again, all the hung-up email was downloaded to my iPhone. Just be patient to let the verification complete and wait a couple of minutes to let the server download. Working hypothesis is that Apple downloaded something that messed up a couple of settings.
Also I used the POP settings with SSL On for the incoming server, not the recommended IMAP settings.
The article with the settings is Configure Your Email Settings to Comcast Email, at
Same problem here.
I solved it by checking the settings and resetting a couple of them according to an article - and magically everything is fine again, all the hung-up email was downloaded to my iPhone. Just be patient to let the verification complete and wait a couple of minutes to let the server download. Working hypothesis is that Apple downloaded something that messed up a couple of settings.
Also I used the POP settings with SSL On for the incoming server, not the recommended IMAP settings.
The article with the settings is Configure Your Email Settings to Comcast Email, at
http://customer.xfinity.com/help-and-support/internet/email-client-programs-with-xfinity-email/
Good Luck