Knowledgebase
How to fix the IMAP error 0x800CCC0E when receiving mail with Outlook
There might be several reasons for getting an error message containing the error code 0x800CCC0E when receiving mail through an IMAP incoming server with Microsoft Outlook as your email client. The whole error message looks something like this (with slight differences depending on the Outlook version):
Task 'Checking for new mail in subscribed folders on your_account.com.' reported error (0x800CCC0E): 'Outlook is unable to download folder (null) from IMAP e-mail server for account your_account.com. Error: Unable to connect to the server. If you continue to receive this message, contact your server administrator or Internet service provider (ISP).'
First of all, check your Internet connection. If you're disconnected from the Internet you'll get the same error code.
The next thing to do is to check the settings for the email account in Outlook. Check whether the names of the mail servers are correct. One reason for receiving the above mentioned error code is wrong port numbers. For example, if you have enabled encryption, but you have changed the port number to 143, which is the IMAP non-encryption port number; or if you haven't enabled encryption but you have set the port number to 993, which is the encryption port number. In the case of Outlook 2002 and Outlook 2003 there is only one checkbox for enabling encryption for the incoming IMAP server. So if you have enabled encryption make sure the port number is 993, and if you haven't enabled encryption the port number should be 143.
In Outlook 2007 and Outlook 2010 there is a drop-down menu from which you can choose between SSL and TLS for encrypting the connection with the IMAP incoming server. Both SSL and TLS are encryption protocols that work on port 993, but what is meant here by TLS is STARTTLS, which works on the non-encryption port 143. So if you have set Outlook 2007 or Outlook 2010 to use IMAP with TLS on the encryption port 993, you'll get the same error message. You have to either set the port number to 143, or select SSL from the drop-down menu and set the port number to 993.
With the same issue with wrong port numbers in Outlook 2010 you won't actually receive an error code but just a message saying that either the operation timed out, or that a secure connection to the server could not be established.
If the error persists, another thing that can cause errors is your antivirus application or your firewall. Either disable the scanning of emails from the application, or stop/uninstall temporarily any antivirus applications/firewalls and test your email account again.
You may find helpful the tutorial on port numbers and SSL/TLS. If you need help with configuring your Outlook check out the article or tutorial on the particular Outlook version.