can't send or receive IMAP/POP mail in Mac Mail
I have configured a new e-mail address with Rackspace using IMAP. They have confirmed all setting are correct. However, I cannot send or receive email using Mac Mail. Have spent almost 2 hours on this. Have repeatedly deleted and re-added the account using correct settings with no change. Any help is appreciated.
iMac 21.5″, macOS 10.13