Not receiving Outlook emails

I have been using eM Client for a while now, with one Outlook and one gmail account, with no problems at all.
Today, suddenly, my Outlook emails are not coming through, and there is a Red Triangle alongside the Inbox for Outlook, that say unable to connect to server ?
Does anybody have any idea why this issue should suddenly occur ?
It is my main Account and it has lots of folders, so I don’t want to delete the Account, and add it again ?

Any suggestions welcomed :slight_smile:


What is happening is that the oAuth certificate is failing.

If you have an application that is not using oAuth, like MS Outlook or your phone, it will work.

Please be patient while we find out more about why this is happening with oAuth.

Hi Gary,
I am using eM Client on a Windows 10 Laptop ?
I did have Mailwasher Free installed, but I have uninstalled it now, in case it was the problem ?
The only thing that also happened today was an Update to AVG Free ?
Not sure if either of these could have suddenly caused the issue ?

And I have just sent an email from Outlook to my gmail address, and eM Client received it fine ?
So it is clearly only the Outlook address that is not functioning ?

Thanks for confirming that.

Yes, it is the oAuth certificate through Microsoft that is the issue. So this will affect addresses on domains like, etc.

Gmail’s oAuth certificates are just fine.


So, do you mean everybody using those domains will be having the same issues in eM Client ?
Or is it just my Account Settings etc ?

It’s everyone. I’m having the same issues. or any email with a domain hosted by outlook. For example, I have a custom domain that uses the backbone.


At least that is a bit of a relief, if it means that eM Client will need to fix it ?
Still frustrating though ! Perhaps a message to all members would be good, if possible ?


The problem is not eM Client.

Microsoft broke something, so their server is no longer authenticating using the certificate they previously provided you with.

They need to fix it.

Best way forward is probably for you to contact Microsoft and ask for assistance.

I’m confused Gary ? My Outlook emails are still being received in Outlook, it’s just my eM Client that is not receiving them, and telling me that it can’t connect to the Server ?

Is it not reasonable to ask that eM Client contact Microsoft to resolve this ? Especially, as it is all your Members having this issue ?


Is your MS Outlook application using aAuth?

I just Logged on to it in Chrome Browser ?

Is there a setting that would tell me that ?

When you say your emails are still being received in Outlook, you mean the web interface, not MS Outlook?

The web interface is not using oAuth. It will use username/password, so it is not the same thing.

The issue is with the Microsoft server and authenticating using oAuth. So this will affect any email application where the account is setup using oAuth for authentication.

I still think, bearing in mind, that this just suddenly arose as a Fault in eM Client, and appears to affect every user of Microsoft email Domains ?
Then surely it is Best Addressed by eM Client advising Microsoft so they can reverse whatever they did to the Certificates ?
The alternative, you suggested, means each and every one of us with this Fault, would have to contact Microsoft ?
Are you aware, if this same issue affects other Mail Client Programs ?


Yes, I am having the same issue. I use my email for work every day all day. Contacting Microsoft will be difficult. I hope someone will fix this or eM Client will lose thousands of customers.

The issue is not eM Client.

You can setup the account in eM Client without using Microsoft’s oAuth certificate, and it will work just fine.

To do that, go to Menu > Accounts and add an account.
Instead of using the Automatic Setup, choose Mail > Other.

You will need the IMAP and SMTP server addresses, and they are:

All other settings will be automatic.

You can use that until you contact Microsoft, or they fix their error automatically.


I’m having the same problem. I hope that eM Client can help get this fixed since I really like using it for my email.

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Mine is the same too and it even happened on my android phone, but that cleared up and is working now.

I received an email from Microsoft maybe 1 week ago stating there was a security flaw in some kind of database thing and hackers could red email, files on one drive etc so they were clearing out of all the certificates

Maybe today is the day theyve done it?

But going crazy with emclient and I get NO Microsoft emails on 5 of my Microsoft accounts!

Gates to busy backtracking his relationship with Epstein I guess instead of worrying about his baby!


As of last night, I can no longer access my hotmail / outlook accounts.

Usually this resolves itself after just clicking the icon, but not this time. It’s persistent, and affects multiple accounts. I can access the accounts manually through the web interface.


Today em client keeps failing to connect to microsoft servers. looked through the forums and found the fix for win and mac. This hasn’t worked for me. I have deleted the email and re added my email clicking the exchange button and I have gone through the setup and when I click finish it asks for my password again. Can anyone help with this please?