Outlook bug?

Question

Hello,

For an customer i have an issue.

Basics:

MS/Office 365 (latest release)
Windows 10 (also 11/server2022)

2 Mail accounts at Exchange online/365 with 3 months cache.

The issue:

User has 2 mail accounts in his outlook profile. His user mailbox (Usr@domein) that is assignt by SSO after login and an second mailaccount (mb@domein) from the same domain. Not it is not an shared mailbox,

The mb@domein is set as default, because they mail from that account. This way when you mail, it always the one in From field. The user@deomin is secondary.

When creating mail in outlook, the mail is sent to the correct folder (sent items) of that user.

But when you create an new email outside outlook, for an third party application, of from explorer (right mouse button > send to > mail recipient), the sent mail is not sent to the correct "sent Items" folder. It is moved to the user instead of mb.

When you flip the from address to user and then back to mb, it works also correcty

But when you change the default to user, create email from explorer, and change the from field to mb, than it works correctly.

The whole reason to set an account as default, that they dont need to change the "from" address.

We tested this with our environment (not the customers), tried it locally and on their citrix environment, its all the same result.

Is this bug (or feature?) or just an wrong setting somewhere?

Answer 1

Hi @Hilbert Pijl ,

When you set up one or more email accounts for a profile in Microsoft Outlook, email messages that are intended for a particular account are sent to the Inbox of a different account.

This issue occurs if the .ost file that's created by Outlook Cached Exchange Mode contains a folder mapping error. Specifically, if the .ost file contains more than one MAPI mailbox, mail may be redirected to an incorrect MAPI mailbox.

Make sure that the default email is consistent with the .ost file.

Go to File > Account Settings > Account Settings > Email tab & Data file tab.

If you have any further updates on this issue, please feel free to post back.

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