A program is trying to access e-mail addresses ...
This is either virus/spyware trying to hack into your addresses or you have installed some version of ActiveSync or similar mobile phone software that is trying to sync with your system.
I have had a similar problem with AVG and the email scanner becoming a bit fubar because of spyware.
Run a full system scan, if you find nothing nothing just try deleting the account and setting it up again.
If you are using Outlook then you can go to Tools> Email Accounts> View existing email accounts> Highlight the account and click change> then Test Account settings - if it fails to complete all tests then something has changed your username and/or password.
Delete and set up account again.
