Based on reviewing Microsoft troubleshooting forums, it looks like general advice for this situation is to try re-syncing the specific folder, or a full resync. Some respondents indicated that a specific email or emails was the cause of the problem - the error message may help narrow down which email. I'd try to resync the folder a few times, and if not follow the troubleshooting advice here and here. Hope that helps!
Based on reviewing Microsoft troubleshooting forums, it looks like general advice for this situation is to try re-syncing the specific folder, or a full resync. Some respondents indicated that a specific email or emails was the cause of the problem - the error message may help narrow down which email. I'd try to resync the folder a few times, and if not follow the troubleshooting advice here and here. Hope that helps!