Outlook group email stops working since 26 Jun 2022

[CL939999]

I have a group email address working for more than 6 months but all of a sudden emails cannot be delivered since last weekend. I'm getting below error code:

Delivery has failed to these recipients or groups:

XXXXX (email address removed for privacy reasons)
The recipient's email system isn't accepting messag...

Diagnostic information for administrators:

Generating server: TYZPR06MB4301.apcprd06.prod.outlook.com
Total retry attempts: 4

XXXXX (email address removed for privacy reasons)
Remote Server returned '421 4.3.2 Service not avail...

Original message headers:

Received: from PS2PR06MB2936.apcprd06.prod.outlook.com (2603:1096:300:53::15)
 by TYZPR06MB4301.apcprd06.prod.outlook.com (2603:1096:400:66::14) with
 Microsoft SMTP Server (version=TLS1_2,
 cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5373.16; Tue, 28 Jun
 2022 01:22:59 +0000
Received: from TYZPR06MB5225.apcprd06.prod.outlook.com (2603:1096:400:1fa::9)
 by PS2PR06MB2936.apcprd06.prod.outlook.com (2603:1096:300:53::15) with
 Microsoft SMTP Server (version=TLS1_2,
 cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5373.15; Tue, 28 Jun
 2022 01:21:57 +0000
Received: from TYZPR06MB5225.apcprd06.prod.outlook.com
 ([fe80::f9c2:d2b7:8283:64c2]) by TYZPR06MB5225.apcprd06.prod.outlook.com
 ([fe80::f9c2:d2b7:8283:64c2%9]) with mapi id 15.20.5373.018; Tue, 28 Jun 2022
 01:21:57 +0000
Content-Type: application/ms-tnef; name="winmail.dat"
Content-Transfer-Encoding: binary
From: xxxx
To: XXXXX (email address removed for privacy reasons)
Subject: testing
Thread-Topic: testing
Thread-Inde...

[#2]

I'm having the same issue, very annoying. Sorry I have no help to offer but hoping someone else can give us some clarity on solving this issue.

[#3 · Accepted solution]

Hi all, it was outlook outage. Please refer to below service status from Microsoft.
https://portal.office.com/ServiceStatus

[#4]

@CL939999  are you still having the issue? I am and I'm pretty sure it's past the time that the "outage" was supposed to be.

[#5]

@Rougheon Yes, the problem still. 

[#6]

I double checked the link and see there's an update that they are still trying to solve the issue. Apologies, I saw this after I messaged you.

[#7]

@CL939999 

I have noticed the same error; our last successful send to an Outlook group was on June 24.  The issue was reported on the Admin Center yesterday and the result was that there was no issue found.  Created a new "test" group today and have the identical problem.

[#8]

I still have the issue and have also created a new group with no joy.

Due for the next update 5 July

[#9]

It took so long time and still not resolved. I just can't believe it happened to a business level Saas platform hosted by Microsoft. I never experienced the same with big tech companies like Google, FB or Amazon.

[#10]

I cannot understand why it is taking so long but also, having opened a case with support, there are no updates issued by MS - it took about 30 minutes to get this far - and then why if you have a case number you can't simply input that and see what the current situation is... they don't make problem solving easy do they?

[#11]

I am having the failure to send for at least two weeks for my group email on outlook. I cannot find help!

[#12]

@Eileen1710 

I have just received an email from them which says it is sorted BUT IT ISN'T.  Same problem for me, is it the same for you?

[#13]

No resolution for me, I am still unable to message groups.

[#14]

Still no joy....
Diagnostic information for administrators:

Generating server: CY4PR1701MB1783.namprd17.prod.outlook.com
Total retry attempts: 4

email address removed for privacy reasons
Remote Server returned '421 4.3.2 Service not available'