Calendar sync fail

remote server fail on outlook calendar annoys me like hell. can’t find a cure for this.

Hello, this can unfortunately occur if the server is unable to process the request due to a server downtime or heavy load.

Can you please navigate to Tools > Settings > Advanced and enable AirSync logging for more information about the issue?

Enable the logging, save the settings and wait for the issue to reoccur, once you receive the error please restart the application and go back to the advanced settings window and submit the logs to my email, with a reference (URL) link to this forum topic.

Thank you.

I’m getting exactly the same problem and have sent the requested information to Paul but no reply. Pity, I like the app except for these annoying error messages continually popping up.

I too am getting the same problem and like you I have sent the error logs and had no response

Hello Graham, sorry for the belated reply, I have forwarded the received data to our developers for more information, but unfortunately it seems like a server issue.

The 503: Server unavailable error suggest the server is unable to process your request on time as it is too busy or isn’t responding, after the setup timeout interval, this error can be thrown, however eM Client should automatically try to re-try the request, if possible.

This is unfortunately caused by the protocol servers are using for synchronizing with Calendar applications or email clients such as eM Client. The problem is held within the calendar sync and the only option to get rid off the error in this case might be disabling the synchronization service completely for Calendar and Contacts.

I do not sync any calendar or my contacts anyway, so how to turn off all syncing but eMail in eM?

Hello, to disable Calendar and Contacts services you have to re-setup the account as IMAP, which will remove the option to synchronize these items.

By default eM Client synchronizes your account using AirSync, which essentially causes the issue to occur. To setup the account as IMAP navigate to Tools > Accounts > New account, but instead of using the Automatic setup, please select the Mail tab below and select “Other”, proceed with the steps and use the recommended server settings using this link: (select Apps that support IMAP and SMTP).

Hope this helps.

ich habe das Problem auch. Habe ich das richtig verstanden, dass die Deaktivierung des Sync von Kalender und Kontakten die “Lösung” ist. Genau wegen dem Kalender verwende ich ja eM-Client! Gibt es inzwischen eine andere, bessere Lösung?

Hello Michael, this issue is caused by the server’s inability to process the request on time or when it experiences down time. Unfortunately as the servers are using a single protocol to sync all your items with the server, it’s not possible to disable the calendar only. However you can re-setup the account as IMAP/SMTP as suggested above, which will allow you to sync e-mail items only.


Since the last update things have got even worst.
I have been running a script
which used to delete the offending popup. Now eM Client just locks several times a day, restarting it makes it work again, I wish I could find an alternative program that is a good as eM Client (when it is working)!!!

Hello Paul, you can setup the account as IMAP to avoid issues with the AirSync protocol which is now setup by default as it supports both calendar and email synchronisation.

We’re working on a new release of eM Client which will be handling accounts a bit differently and will synchronise your mail data over the IMAP/SMTP protocol as well - however it will include your Calendars and Contacts synchronised over the AirSync protocol.–…


Hello Paul,  I seem to have solved my problem. It was mainly the calendar the would not sync, so at your suggestion I have made my account an IMAP account.
I have a gmail account that I don’t use for much for email.
I have discovered that in eM Client I can select only contacts and calendars for my gmail account, so I have moved all my contacts and calendar events over to gmail.
 Thanks for your prompt replies

Hello Paul, glad you were able to resolve the problem, please make sure to let us know if you come across any other issues or questions about the application, we’ll be happy to help.