Outlook 2016 Issue with 2 Exchange accounts with different domains RRS feed

  • Question

  • Hi,

    We have an unusual issue that keep occurring for one of our customers and I am hoping that someone can help. I originally posted in a different forum and they suggested I post here due to the Exchange aspect.

    The environment:

    Office 365 - the account/software is activated with account <user>@onmicrosoft.domain.com

    He has four mail accounts - 2 Exchange and 2 IMAP accounts - the issue appears exclusively with the Exchange accounts. It is important to note that the Exchange accounts are 2 separate domains on completely different environments.

    1 x Domain has Exchange onsite and the computer is joined to this domain.

    1 x Domain is hosted Exchange (not Microsoft)

    Both Exchange servers are 2013, the version of Outlook is 2016 (Office ProPlus 365)

    The error:

    After a period of time - so far it seems to be within a two week period, one of the Exchange Mailboxes will not expand. Additionally for the mailbox that is expanding you get a password prompt when you start Outlook up trying to start up with "Microsoft Account\email address" (email address is the primary email address - so whichever Exchange we set up first). The password prompt does not allow you to continue, if you cancel you get into Outlook and it will connect Exchange Mailbox no.1 and send and receive but not no.2. You may still get a prompt but if you put the correct password in it connects for a time and sends and receives.

    Another important piece of information is that the mailbox that will not expand is always the secondary mailbox. So whichever is set up as the primary continues to work (albeit prompting for password) but the second exchange mailbox is always the one that will not expand. We have tried setting each one as primary and the domain makes no difference, it is the secondary one that stops being able to expand.

    If you remove the Exchange account that will not expand, the Outlook Profile corrupts entirely and you have to start from scratch. No options despite many attempts to get it working again.

    We have removed all credentials from Credential Manager and inputted them fresh - makes no difference.

    The last time this was set up the accounts were added using the full UPN - issue returned.

    We have scratched our collective heads about this one and spent considerable time investigating but haven't been able to have a permanent solution. If anyone has any ideas that might help I would be extremely grateful.



    Monday, May 29, 2017 12:08 AM

All replies

  • Honestly and seriously, I'm surprised that what you're doing works at all because it is my experience that Outlook doesn't serve two masters well.  My recommendation is always use separate profiles for different Exchange Server accounts.

    Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."
    Celebrating 20 years of providing Exchange peer support!

    • Proposed as answer by Allen_WangJF Monday, June 5, 2017 3:29 PM
    Monday, May 29, 2017 5:08 AM
  • Hello John,

    Agree with Ed, since all works fine while Outlook with one single account, thus this issue is more related to Outlook client.

    Also, I recommend to separate Outlook profile with those mail account to prevent unexpected issue.
    Here's a reference link about Add multiple Exchange accounts in the same Outlook profile:

    Best Regards,

    Allen Wang

    Please remember to mark the replies as answers if they help.
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    • Proposed as answer by Allen_WangJF Monday, June 5, 2017 3:29 PM
    Tuesday, May 30, 2017 8:34 AM