Problem Description
- Your mail app (like Outlook or Apple Mail) is unable to connect to the server to retrieve new messages, yet it was working very recently
- You have double and triple checked that your mail settings match the mail settings reference article.
- This occurs intermittently such that one day you cannot obtain new messages and later that day or the next day it works fine
Problem Resolution
This issue most commonly occurs when the server's firewall is blocking your IP address for repeated failures to login to any one or more mail accounts. When this occurs enough times, the firewall considers it an attempt to hack your mail passwords, and blocks the IP to prevent it from being able to try other options. The block is typically for 30-60 minutes, however after enough temporary blocks, the block is likely to be made permanent.
Please read our article on how to unblock and/or whitelist your IP. Although the IP can be whitelisted, it's only a stopgap as most IPs are dynamic, so once your Internet provider changes the IP, you'll be back at square one with your failing connection attempts triggering firewall blocks from a new IP.
The solution here is to find the device where those accounts are configured with the wrong credentials and remove them or correct the credentials. The most common scenarios where this occurs are:
- When you have another mail app that has the account(s) configured other than your primary one (example: Apple Mail was once setup to access these accounts, but you now use Outlook).
- At one point the accounts were configured with different settings and rather than removing the old settings, you added a totally new account, leaving the old one in place.
- You have the accounts configured on an old device (phone, tablet, or computer) that either a) runs an outdated operating system that can no longer connect to the accounts due to insufficient security protocols, or b) still has old connection settings configured
Regardless of which is the source of the issue, the solution is to stop those accounts from attempting to login with the wrong information by either disabling them, or removing them from your mail app.
