The mailbox may have some emails with an excessively long subject line that are not supported by Windows Phone 8. Once you have removed the suspect mail item (i.e. cleaned the mailbox or move the suspect mail to a folder that phone does not sync) the error will cease.
- Can I get a notification if I receive call or text messages from blocked numbers?
- How can I remove a number from the blocked list in the call+SMS filter app?
- How do I take a screenshot of the current window on my Lumia phone?
- Can I block phone calls from private numbers using the call+SMS filter app?
- What is the call+SMS filter application on my Lumia device?