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Out of the blue I am unable to log into the Exchange ECP page. It brings up the logon page then thinks about it for a few seconds before giving me a 404.503 - Not found error.
I recently updated to CU23, but after this I was able to log in just fine.
The reason I need to log in is we found a shared mailbox we do not recognize, the email address is not in our namespace and I am unable to delete it in EOL because it is syncing from the on premises server. The mailbox appears to have been created before the CU23 update so it is not a case of someone hacking in, creating this and denying access.
How can I fix the 404 error and is there another way to delete the shared mailbox without deleting all shared mailboxes?
we found a shared mailbox we do not recognize, the email address is not in our namespace and I am unable to delete it in EOL because it is syncing from the on premises server.
Could you provide detailed information about this one? Such as where did you see this shared mailbox?
I also want to confirm with you that whether you could open EMS (Exchange management shell) successfully?
The mailbox was listed in Exchange online under shared mailboxes.
Yes, I was able to open ECS, as I said I had run remove- and disable- cmdlets in ECS with no success.
I have now posted how I resolved this, they were 2 separate issues, one was a pretty easy fix once it was seen, the other was longer withfar more steps but ultimately resolved the issue
Depends on what you mean by delete:
I would prefer to mail disable the account, but as stated I can't get in to the admin console for the on prem server.
The mailbox is associated with a valid user account, long story short they work for a subsidiary and log into our domain but have email in a different namespace not associated with us. The AD account needs to remain active but the mailbox needs to go away.
If I try to delete the mailbox in EOL, using either the console or powershell it gives me the error
The following error occurred during validation in agent 'Windows LiveId Agent': 'Unable to perform the save operation.
'user name' is not within a valid server write scope.
So I'm at a loss as to a) how this was created and b) how to remove it.
Hi there.
So I would use on-prem Powershell and connect to the on-prem Exch Server
then run:
https://learn.microsoft.com/en-us/powershell/module/exchange/disable-remotemailbox?view=exchange-ps
Disable-RemoteMailbox <remote shared mailbox>
that will remove the shared mailbox in Exchange Online once it syncs via AADConnect, but leave the AD Account intact.
This gets more confusing.
If I run disable-remotemailbox or remove-remotemailbox on the local exchange server it tells me the mailbox cannot be found.
So I have this shared mailbox that shouldn't exist, cannot be removed in EOL or on the local server and doesn't appear to be attached to the AD account using the same user name.
I am also still unable to log into the Exchange ECP, which is actually a bigger issue.
So I solved both issues.
ECP access - My boss had tried to add a filter to the IP address and domain restrictions in IIS, but had then left Edit Feature Settings disabled. As soon as this was enabled access to ECP came back.
The rogue shared email - I gave the AD account an O365 license, changed the mail, proxy addresses and target address attributes so he had a primary address within our namespace, waited for AADC to sync and for EOL to show the changes. I then converted the now valid shared mailbox to a user mailbox, removed the license and waited for the AADC sync to run again. The mailbox has gone away.