Detailed error message: Exception happened when doing AAD dual-write.

[Marvin Oco]

trying to delete and add contacts in 365, got error below

An Azure Active Directory call was made to keep object in sync between Azure Active Directory and Exchange Online. However, it failed. Detailed error message: Exception happened when doing AAD dual-write. For more details, please check RemoteException if using RPS client or innerException otherwise. RequestId : e8586e36-6c20-488d-1eca The issue may be transient and please retry a couple of minutes later. If issue persists, please see exception members for more information.

we have ad connect server but only users are synched.

contacts are added directly in 365'

any known  fix?

[#2]

@Marvin Oco I'm having the same issue when attempting to create a new group. I don't have AD setup yet. 

[#3]

not sure if this is global issue, this is working before.
already submitted ticket to microsoft, still waiting for solution.

[#4]

Okay, thanks. Please update when you hear from MS.

[#5]

tested also in my tenant, cannot add new distribution list

[#6]

@Marvin Oco 

Same error when trying to convert user mailbox to shared mailbox, when edit Aliases in user mailbox.

All work has stopped.

[#7]

Same issues here, on with MS now. I dont think they are going to help, sounds like we are waiting for a fix on their end. 

[#8]

@Vladimirkomsaras I have the same error when trying to convert a user mailbox to shared mailbox.

[#9]

@Marvin Oco 

Check if your tenant is impacted by SI EX235961.

[#10]

@Marvin Oco the issue apply in my tenant, when i changed the mail or named UserName, I call the support of Microsoft but the reponse was "need a evidence" and I detail the failure, I waiting a response or the solution to fix this error, Any has the same mistake?

[#11]

@sububi The conversion just worked without any prior corrective actions.

[#12]

@Marvin Oco 

I'm fine again 😉

[#13]

@LiVe33 

Yes!   All functions work now.   

[#14]

Thanks All, mine is working now too. 

[#15]

Although I was able to add a new group, I'm still having trouble managing the group (add users).

[#16]

disregard. might be a browser issue. closed and reopened my browser and it allowed me to manage groups again. 

[#17]

this is because of recent update from MS that they have enabled dual write feature for all tenants and this will be permanent feature as of now.
https://techcommunity.microsoft.com/t5/exchange-team-blog/exchange-online-improvements-to-accelerate...

I faced various issues like not able to add alias.

Getting error: Another object with the same value for property EmailAddresses already exists.
The issue may be transient and please retry a couple of minutes later. If issue persists, please see exception members for more information.
Cmdlet-UnableToWriteToAadException]

If you look at the error details it says "UnableToWriteToAadException". When we connect to powershell of the tenant and run command:
- Ran command: Get-OrganizationConfig | fl IsDualWriteEnabled
IsDualWriteEnabled : True

A support ticket and you need to tell MS to disable the feature. Then you can remove shared mailbox.

[#18]

ok now in my tenant

might be related to incident EX235961.

[#19]

@Marvin Oco 

I have this issue now again 😞