New Office 365 Mailbox Errors

Rupert Eghardt
Rupert Eghardt used Ask the Experts™
Hi Guys,

We are having an issue with two mailboxes in Office 365.
These are brand new mailboxes - not migrated and not linked to onsite AD.

We setup the mailboxes successfully on the mobile phones, but setting the profiles up in Outlook failed.
Logging into the mailboxes online, resulted in an error:
Something went wrong, please try again again ... err:  Microsoft.Exchange.Data.Directory,ForestUnavailableException

After a password reset on one of the mailboxes, it asked for the time zone (logging on online)
After the time zone select we are getting "401- Unauthorized:  Access is denied due to invalid credentials"

We spoke to Microsoft, but they are not of much help up to this point.

Any ideas will be appreciated,
There are unfortunately already new mail in these mailboxes, and deleting / recreating these mailboxes are not an option
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I am surprised MS was not much help. I have several clients I have set up O365 for and I have had great success with their phone support. I would try calling back to get somebody else.

Before you do that, it sounds like you are working with multiple users.  There is something about logging in with multiple accounts on one browser that seems to make things crash. Try logging in using a private browser. When you get to the prompt for business/school or personal, make sure to select business/school.   When you do log out, make sure to close the browser before logging in to another account even when  using private browsing.
Rupert EghardtProgrammer


Thank you, we spend a couple of hours with MS on the phone.
Eventually gave up on these two mailboxes.

We created two new mailboxes, forwarded the mail from the mobile devices and deleted and recreated the mailboxes altogether.

All seems to be working now ... still not reason or solution to the problem.

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