Error message - so many

So many error messages: why?
1:04:55 PM Online state: changed to online due to NetworkAvailability
1:04:55 PM [email protected] IMAP Synchronizing folder list
1:05:29 PM [email protected] IMAP Uploading item(s) to folder ‘/Inbox’
1:05:34 PM [email protected] [IMAP] MailClient.Storage.Application.ItemOperationException: BAD [CLIENTBUG] APPEND Invalid message date from client
1:05:34 PM [email protected] IMAP Synchronizing folder ‘/Inbox’
1:06:01 PM [email protected] IMAP Synchronizing folder ‘/Sent’