Sudden slowdown in communication with the server

eM Client had been working well (after several weeks of problems) for several months, but last week (end of March) I began to notice considerable slowdowns when I selected a message for viewing.  There did seem to be more synchronization errors with the Microsoft server, but when eM Client issued another request, it usually succeeded.  But this issue is with messages for which the headers are already downloaded.  When I click on them in the left pane, they are slow to display in the right pane: and I mean really slow.  Somwtimes they never manage to display.  It appears that eM Client is just spinning its digital wheels.  

At first I suspected my internet connection, but when I checked it was working properly.  I do only have about .7mbps speed, but as I mentioned, that has been sufficient in the past.  So what has changed?  I don’t know and I wonder if anyone else has experienced such a slowdown.  I do have quite a few messages in my inbox.  [around 2000].  Is there a limit that causes such slowdowns?

Sometimes the message fails to load at all.  Here is the log from such an instance:

10:15:41 AM [email protected] [IMAP]  Copying messages10:15:41 AM [email protected] [IMAP]  Downloading message part…
10:16:06 AM [email protected] [IMAP]  Copying messages: Done
10:16:06 AM [email protected] [IMAP]  MailClient.Accounts.ConnectionException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host. —> System.IO.IOException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host. —> System.Net.Sockets.SocketException: An existing connection was forcibly closed by the remote host
10:16:06 AM    at System.Net.Sockets.Socket.Receive(Byte[] buffer, Int32 offset, Int32 size, SocketFlags socketFlags)
10:16:06 AM    at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size)
10:16:06 AM    — End of inner exception stack trace —
10:16:06 AM    at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size)
10:16:06 AM    at System.Net.FixedSizeReader.ReadPacket(Byte[] buffer, Int32 offset, Int32 count)
10:16:06 AM    at System.Net.Security.SslState.StartReceiveBlob(Byte[] buffer, AsyncProtocolRequest asyncRequest)
10:16:06 AM    at System.Net.Security.SslState.CheckCompletionBeforeNextReceive(ProtocolToken message, AsyncProtocolRequest asyncRequest)
10:16:06 AM    at System.Net.Security.SslState.StartSendBlob(Byte[] incoming, Int32 count, AsyncProtocolRequest asyncRequest)
10:16:06 AM    at System.Net.Security.SslState.ForceAuthentication(Boolean receiveFirst, Byte[] buffer, AsyncProtocolRequest asyncRequest)
10:16:06 AM    at System.Net.Security.SslState.ProcessAuthentication(LazyAsyncResult lazyResult)
10:16:06 AM    at System.Net.Security.SslStream.AuthenticateAsClient(String targetHost, X509CertificateCollection clientCertificates, SslProtocols enabledSslProtocols, Boolean checkCertificateRevocation)
10:16:06 AM    at MailClient.Imap.Base.Connection.<>c__DisplayClass43_0.b__0()
10:16:06 AM at MailClient.Imap.Base.Connection.Connect(Func1 getStream)<br>10:16:06 AM at MailClient.Imap.Base.Connection.Connect(String receiveHost, Int32 receivePort, Boolean explicitSsl)<br>10:16:06 AM at MailClient.Protocols.Imap.ConnectionPoolEntry.Reconnect(CancellationToken cancellationToken)<br>10:16:06 AM --- End of inner exception stack trace ---<br>10:16:06 AM at MailClient.Protocols.Imap.ConnectionPoolEntry.Reconnect(CancellationToken cancellationToken)<br>10:16:06 AM at MailClient.Protocols.Imap.ConnectionPoolEntry.Connect(CancellationToken cancellationToken)<br>10:16:06 AM at MailClient.Protocols.Imap.ConnectionPool.AcquireConnection(Folder mailFolder, Boolean idle, Boolean forStore)<br>10:16:06 AM at MailClient.Protocols.Imap.ConnectionContext..ctor(ImapAccount account, Folder folder, Boolean forStore)<br>10:16:06 AM at MailClient.Protocols.Imap.Synchronizer.FolderInfo.CreateConnectionContext()<br>10:16:06 AM at MailClient.Protocols.Imap.Synchronizer.CopyCommand.ProcessCopy(WorkerStatus status, FolderInfo sourceFolderInfo, IList1 items, SequenceSet sequences)
10:16:06 AM at MailClient.Protocols.Imap.Synchronizer.CopyCommand.ExecuteInternal(WorkerStatus status)
10:16:06 AM at MailClient.Protocols.Imap.Synchronizer.ImapCommand.Execute(WorkerStatus status)
10:16:06 AM at MailClient.Commands.Command.Process(WorkerStatus status)


I have to second that.  I am using version 7.0.27943.0.  Beginning the last week of March through today my eM Client seems to be having a problem with the Microsoft server(s).  Synchronization of Outlook folders is very slow and opening an email takes a long time.  Also, when I try to move an email from an Outlook folder to a local folder the transfer can take minutes or the transfer fails. doesn’t indicate any problem with the Microsoft mail servers at the time that I am using eM Client.       

Need to setup account as Exchange. See the following thread:…

Affects all Microsoft accounts (MSN, Hotmail,

OK-- So the answer is Microsoft changed their protocol and didn’t tell us to change ours and neither did eM Client even though they must have been aware of this issue.  Bad service on the part of both organizations.  This link shows the steps to go through to make the necessary change:

However, one will then have two versions of the same email mailboxes.  I think once the new account is fully synchronized, the original count should be removed.  Hopefully, this will not result in the loss of any wanted messages.  How does one know that they have switched to EXCHANGE?  This did not show up in my case in the accounts settings and in fact, the IMAP and SMTP settings are the same for the original account and the new account.

Exchange is a completely different protocol than IMAP, it’s not just a port and security setting change.  The added benefit of Exchange vs. IMAP is that calendars and contacts will sync, whereas with IMAP they would not.

Microsoft’s switch to Exchange has been well documented over the last year in this forum and many others, so it really should not have come as a big surprise.  However, it seems as if Microsoft changed some of its internal implementation of IMAP, causing a recent problem for those users.  That being said, I’m not sure how eM Client could be responsible for notifying customers every time an email provider changed its internal protocols.


I was confused in my original reply about the port settings etc., and I went back and edited it.  I think you are relying to the original version.  The port settings are all the same in both accounts and that makes me wonder if the conversion to EXCHANGE actually occurred.  Is there a way to determine that?

As far as eM Client’s responsibilities to its users, I suppose that is an organizational issue.  I am pretty sure that if the service is not smooth and efficient, people will stop using it.  I know that is the case for me.  I have been tempted to drop this service several times since I started using it 5 years ago.  I have stayed with it only because I have so much of my life invested in it.  I don’t think the number of users depending on Microsoft mail is insignificant.  Therefore, I would expect eM Client to make more of an effort to facilitate changes to the MSN protocols that cripple eM Client performance and inform the affected users about the problem and the solution.  Updates are (or used to be) announced by email.  Why not fixes to problems?  A user should not have to be constantly reading or referring to this forum in order to keep his email functional.

Hi Tom:-- I’m pretty sure that all of the Microsoft accounts have been migrated to Exchange.  I’m not sure how to verify this with an MSN account, other than setting it up and seeing if it works (since you do not have to get rid of the IMAP account to set up a new Exchange account).

I’m not sure who eM Client would notify and how they would do it.  I think it is the responsibility of the email provider to notify its clients, as they are the ones directly affected.  I’m sure eM Client relied on this forum for “notification”.

I’m also pretty sure Microsoft did notify its customers.

Jay-- Someone else posted the way to tell if you have been migrated to exchange by Microsoft.  Using the OUTLOOK.COM browser based mail program, check the upper left corner to see if it says “Outlook Mail” on the black header bar.  That is the indication that your account has been migrated.  BTW:  The talk on the forum at the time Microsoft was changing things was to switch your account from airsynch to IMAP.  I did that.  Since then I have not received notice from Microsoft about changes, but apparently there was one that became an issue for IMAP users around two weeks ago.

As for my situation at present,  I went back and deleted the additional account I had created, and added one that says it is an exchange account.   However, it is not showing up in the left hand column of the eM Client display.  At first I thought it might have integrated with the original account, but the performance issue is still there.  I have selected the Exchange account as the default, but that did not change anything.  Not sure what to try next.

Yeah, I get that about accounts, but the context here was an msn account.  I don’t use either, so I’m not sure if there is a way to tell if an MSN account has been migrated.  Originally, Microsoft quite supporting Airsync and they had not moved everyone to Exchange, so IMAP was the only solution for those in between Airsync and Exchange.

Getting back to your issue, not sure why you are still seeing performance issue and I don’t understand about not showing up the left-hand panel.  Screen shot?

I don’t think a screen shot would convey anything much except that there is only one inbox – the one for the original IMAP based account.  And that is the only account that seems to be doing anything.  When I created the Exchange version (same email address) it did not populate or create another set of folders.  Here are some of the lines in the most recent log.  If you care to look at it I think you can see that things are not going too well.  The last entry is at 3:29:36 and it is now 3:37 and the synchronization of the inbox has still not completed.  If you look at 3:27:56 and following you can see how long it is taking to download a message.  This used to be almost instantaneous.  On some of the shorter durations above I terminated the download by selecting a different message when there seemed to be nothing happening.

1:34:20 PM [email protected] [IMAP]  Synchronizing message flags: For folder [email protected]/Inbox1:34:25 PM [email protected] [IMAP]  Synchronizing message flags: Done
1:39:02 PM [email protected] [IMAP]  Synchronizing messages: For folder [email protected]/Inbox
1:39:48 PM [email protected] [IMAP]  Downloading message part…
1:39:59 PM [email protected] [IMAP]  Downloading message part…: Done
1:40:00 PM [email protected] [IMAP]  Downloading message part…
1:40:06 PM [email protected] [IMAP]  Downloading message part…: Done
3:27:56 PM [email protected] [IMAP]  Downloading message part…
3:28:19 PM [email protected] [IMAP]  Downloading message part…: Done
3:28:46 PM [email protected] [IMAP]  Synchronizing subfolders: For folder [email protected]/
3:28:46 PM [email protected] [AirSync]  Synchronizing folder ‘[email protected]/Calendar/’
3:28:49 PM   MailClient.Storage.Application.OperationException: Synchronizing folder ‘[email protected]/Calendar/’ failed due to the following error: The remote server returned an error: (500) Internal Server Error. —> System.Net.WebException: The remote server returned an error: (500) Internal Server Error.
3:28:49 PM    at System.Net.HttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
3:28:49 PM    at MailClient.Protocols.AirSync.Protocol.ActiveSyncCommandRequest.GetResponse(CancellationToken cancellationToken)
3:28:49 PM    at MailClient.Protocols.AirSync.AirSyncItemSynchronizer2.Synchronize(IItemSynchronizeContext1 synchronizeContext, Folder folder, CancellationToken cancellationToken)
3:28:49 PM    at MailClient.Protocols.Common.ItemSynchronizer`2.<>c__DisplayClass28_0.b__1(WorkerStatus status, CancellationToken cancellationToken)
3:28:49 PM at MailClient.Protocols.AirSync.AirSyncGenericCommand.Execute(WorkerStatus status)
3:28:49 PM — End of inner exception stack trace —
3:28:49 PM at MailClient.Protocols.AirSync.AirSyncGenericCommand.Execute(WorkerStatus status)
3:28:49 PM at MailClient.Commands.Command.Process(WorkerStatus status)
3:28:54 PM [email protected] [IMAP] Synchronizing subfolders: Done
3:28:54 PM [email protected] [IMAP] Synchronizing subfolders: For folder [email protected]/Inbox
3:29:36 PM [email protected] [IMAP] Synchronizing subfolders: Done
3:29:36 PM [email protected] [IMAP] Synchronizing messages: For folder [email protected]/Inbox

It does not seem like there is any EXCHANGE dialogue going on and it is still trying to use AIRSYNCH to synchronize the calendar.

Yep, this is an IMAP account, not Exchange.  Make sure when you set up the account, do NOT use the automatic setup.  Instead, click on ‘Mail’ and then ‘Exchange’.  Make sure to use your full email address when it prompts for either user name or address.

The reason automatic setup uses IMAP is because there was a time when the transition to Exchange accounts had not been completed and some users had IMAP and some had Exchange.  IMAP was safe, because it would always work.

OK  I give up.   Not only did the last thing I typed in here suddenly disappear, I cannot get a screen shot of the account set up.  You will have to take my word for it that I have two accounts set up in Em Client.  The first one in the list is the original IMAP that I started with.  The second one is the Exchange based one that does not seem to be active even though I have made it the default.  Sorry for bothering you with this.  I have been working on this for hours when I should really be spending the time on my income tax returns.  So that is what I am going to do now.  It is really a sad situation when working on your taxes is easier than reading your email.

I’m really sorry, but my knowledge of exchange account setup is very limited, since I don’t use that type of account.  You might try going to menu/tools/accounts and on the IMAP account (IMAP tab) disable all services.  Just a stab in the dark…

I have an Exchange account as one of the accounts I use with EM Client, and I am having the same issues. In addition, I am having the same issues with my account. Also, synchronizing has been incredibly slow!

Well now the  emClient does not seem to be functioning at all.  But I did get a warning message when I started it up that said diagnostics had been on for more than three days.  There was an option to turn it off which I did.  But now I am wondering where the diagnostic files are and how I can remove them from my hard disk.  Anyone?

c:\users[user_name]\AppData\Roamng\eM Client\Logs.  Make sure you have hidden files set to display.

I change my accounts from IMAP to Exchange and that resolved the problems for my accounts.  However, it appears that my accounts have not been moved to the Exchange server yet, so they could be set up with the Exchange format.