Outlook App opening a browser Tab

Greetings All,

Had the same issue. Disable "Continue running background extensions and apps when Microsoft Edge is closed" and your problem should go away.

Just to add to this, we have some users who use both Firefox and Chrome and this issue is present there. Whatever is causing the issue, is opening the OWA page in the default browser of the the PC so in our case this option doesn't give us a workaround. At least on the on Edge using users.

Hello, we have had some success turning off the setting in Outlook calendar options for the Online Meeting Provider. If you click into this setting there is a checkbox you can "Uncheck" this has stopped the windows opening for our users.

Unfortunately, that did not work for me.

Sorry - Only Troubleshooting steps I received from my ticket with Microsoft have been to Revert office version and change default browser. We have also started getting users with Calendar issues beyond this browser windows opening that has not been solved - inability to type consistently or copy and paste into the meeting invite windows. These users are users with the browser window opening as well.

We are having the same issue, although with some additions. We get users having a browser popup with error 500 when creating new meetings and users having error 400 popup in a browser when they open outlook or try to edit some messages.

I was able to take care of some of the ones related to the meetings with the following regedit in a gpo

Key Path: HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Options\Calendar
Key: ShowLegacyRoomFinder

Type: REG_DWORD

Value: 1

I have noticed that the other errors are occurring on this web page:

https://login.microsoftonline.com/common/oauth2/authorize?client_id=00000002-0000-0ff1-ce00-000000000000&redirect_uri=https%3a%2f%2foutlook.office365.com%2fowa%2f&resource=00000002-0000-0ff1-ce00-000000000000&response_mode=form_post&response_type=code+id_token&scope=openid&msafed=1&msaredir=1&client-request-id=f322cfb1-88cf-79b5-3f43-09e2b277fd8b&protectedtoken=true&claims=%7b%22id_token%22%3a%7b%22xms_cc%22%3a%7b%22values%22%3a%5b%22CP1%22%5d%7d%7d%7d&nonce=638059384817229913.d8a9da8a-7062-4905-ab94-7f8c74284040&state=DctBEoIwDEbhVu7hDWpDG0iycDjLr6iwgHYGZri-XXxv97xzrmtujacWJ2NWGiwray8pmfX5MStshiIIjSmw0RDwMg7y1bdwUiYm3957LBfiVHEuz1jquZb9iBt2_D6o9fgD&sso_reload=true

I can access this webpage fine on my computer, and mine does not get the popup when I open outlook or when I mess with messages like some users do. Like others have said here I have noticed this occurring ever since recent updates.

I also noticed the error occurs if I go to File and then click on the button that says "Manage Add-ins" : "Manage and Acquire Web Add-ins for Outlook".

I have already tried repairing, reinstalling, running outlook with no add-ins enabled, creating a new outlook profile,, flushing dns, clearing browser cache, verifying network settings are correct for the users having the issues.

Email and calendar works, so I am not sure why these browser popups are necessary, especially when opening outlook.

Hope this info helps to find a resolution