Follow these steps to re-connect your Windows account to Outlook.
1) Open Outlook
2) Once Outlook is open, check the bottom right of Outlook, you will see a message stating that it's trying Trying to connect...
3) When Outlook fails to connect to the exchange server, Windows Security should pop up and prompt you for your most recent Windows Password. Put the password in the open field underneath your e-Mail and checkmark the box, Remember my credentials. (If Windows Security does not come up, left click Trying to connect... this will force Windows Security to prompt for credentials)
4) Once you have followed the steps above, you should see that you are Connected to: Microsoft Exchange.