I am getting this in general error log, but no other errors in the other logs.
14:19:40.347 [MAIL SERVICE] Object reference not set to an instance of an object.
at SmarterMail.Protocols.IMAP.IMAPSession.RemoveMailboxDelegates()
at SmarterMail.Protocols.IMAP.IMAPSession.IdleStatusDelegate(List`1 idList)
at MailService.WCF.Messages.StoreMessageFlags(String callingUserEmail, String emailAddress, String folderName, UInt32[] uids, MessageFlagsUpdateData messageFlags, IWcfResult result, MailActionObject signalR, Boolean deleteClientChangeKeyInStore, PidCollectionFile pidsFile, Boolean updateChangeNumAlways)
at MailService.WCF.Services.EMailService.PatchMessages(String emailAddress, String domain, String userName, MessageEditInput input) 14:19:40.370