office 365 accounts constantly synchronizing

My 5 gmail accounts sync quickly and correctly but my 2 Office 365 accounts sync slowly and never stop syncing. Twenty hours a day (yeah, I just work work work) I can see the sync spinning wheels for the gmail accounts occasionally firing up and lasting a few seconds but for the office 365 accounts they sync continually and never stop. My volume of email on those accounts is very light, as in ten emails per day. I am testing eM Client 6.0.20968.0 on two high-end Windows 8.1 u1 computers with the same email accounts. CPU/RAM/disk usage is close to zero.

Hi Harvey, are you having some issues with receiving or sending email with your office 365 accounts?
Or are you having issues with any other features for this account? Are you seeing any errors? How long have you been using eM Client?

Thank you,

  1. I started using eM Client a few days ago. If it works out for me, I will buy Pro (several licenses).

  2. I just did an email test. I tried sending emails in both directions between a Google account and an Office 365 account, and sending emails in both directions between two different Google accounts, all using eM Client. Results: Google-to-Google worked properly. Google-to-Office365 did not make it into the Office365 Inbox or Junk E-mail folders. Office365-to-Google did not make it into any Google mailboxes and in fact did not even make it into the Office365 Sent mailbox. I have no rules set up for the Office 365 account.  I clicked on the Send and Receive All menu selection every so often. 18 minutes have passed and the Google-to-Office365 email and Office365-to-Google email have not arrived.

  3. Yesterday, I did a calendar invite/accept scenario and that worked in both directions, Google-to-Office365 and Office365-to-Google.


WAIT… UPDATE: The Google-to-Office365 email arrived after 20 minutes and the Office365-to-Google email arrived after 21 minutes. The email sent from Office365 still has not appeared in its own Sent folder in eM Client even after 25 minutes; however, it did make it to the Sent folder online (not eM Client) at the 20 minute mark.

I have the synchronization interval set to 10 minutes. During this period, per task manager, CPU usage is 6% for all processes and 0.4% for eM Client, memory utilization is 23% overall and 84.5 MB for eM Client, and disk and network is at 0%.

Have you got any rules set up at all, particularly quite complex ones? You mention ‘I have no rules set up for the Office 365 account’ but I don’t see how a rule can be set to only run on certain accounts unless you run the rule manually. (A missing feature, in my opinion).

I had the identical issue with my Office 365 account, which was solved by removing the complex rule I’d set up.

Hi Nico, you can have a Rule setup to be processed with one account only, when creating the rule you have to select the option “processed with account” and then select the account for which the Rule will be used for.

Hope this helps,

Hi Harvey, can you please try to update to this version of eM Client, there are several bug fixes released in this update, hopefully this might improve the performance .
However I’m not completely sure whether you committed these tests (Google -> Office 365, and backwards) in eM client or in their webmail, can you possibly try to send out the same messages using the web application if the speed improves?

Thank you,

Although I haven’t changed any settings, this morning eM Client suddenly started to work correctly for one of my two Office 365 accounts. Prior to this morning, short text-only emails between my Office 365 and Google Apps/Gmail accounts were taking 20 or more minutes to send and receive, with some emails never arriving even a day later. Now emails involving this one particular Office 365 account is taking just a few seconds instead of dozens of minutes to send and receive. The first mystery is: What changed? I know I didn’t deliberately alter any configuration settings. The second mystery is: Why is the other Office 365 email still experiencing the sluggishness? Both these Office 365 email accounts are on the same domain, both are system admin accounts (no restrictions), and neither account has any email rules defined.

[1] Using eM Client…

Sending from gmail to o365: I see the email in the Sent folder on gmail, but not in the Inbox of Junk E-mail folder on o365 even after 10 minutes.

Sending from o365 to gmail: I don’t see the email in the Sent folder on o365 or the Inbox or Junk E-mail folder on gmail. However, I am certain that I sent this.

So, I press “Send and Receive all” every so often in eM Client and keep checking inboxes, sent folders, and junk folders every so often. Result: Still nothing after 10 minutes.

[2] After waiting 10 minutes, I log into Office 365 (OWA) using a web browser…

I see that the email sent from gmail to o365 arrived nearly instantly in o365. It’s there in OWA, just not visible in eM Client.

I see that the email sent from o365 to gmail is not in the Sent folder in o365. However, I am quite certain that I sent that email.

[3] At the 15 minute mark, the email sent from gmail to o365 suddenly appeared in the gmail inbox and in the o365 sent folder.


Hi Harvey, does the application become unresponsive at some point? Do you see any errors in the Operations window or in the Log?
What version of eM Client are you currently using?

Can you please go to Tools > Settings > Advanced and turn on Exchange Web Services logging for the problematic account?

  1. Save the settings
  2. Restart the application
  3. Replicate the issue
    If the issue occurs, please go back to the advanced settings window and click on “Send logs” and send the logs to my email with a reference link to this forum topic.

Thank you,