Why can't my iPhone connect to the mail server anymore (and how can I fix it)? A few days ago my iPhone stopped downloading new emails.  The Mail app now brings up an error:

Cannot Get Mail
The connection to the server failed.

Though it can't connect to the server to download or send emails, it can connect to verify my username and password:


This email address is working just fine using my laptop.
Some things I've tried that didn't fix the problem:

going into airplane mode and back out
restarting the device
reentering my mail account settings
deleting the mail account and creating a new one

Some specs:

iPhone 5
iOS 7.1.2
email provider: Yahoo
service provider: AT&amp;T
Settings → General → Reset → Reset Network Settings.