# Microsoft Teams App fails to open from Safari

- URL: https://www.heissenberger.at/en/blog/microsoft-teams-app-fails-open-safari/
- Language: en
- Published: 2022-03-24
- Updated: 2022-06-03
- Tags: Apple, MacOS, Microsoft Teams, Safari, FixIt

> Invitations opened in Safari no longer open Microsoft Teams App with the existing button. But there are workarounds.

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You open a link from an E-Mail or calendar entry for a Microsoft Teams Meeting and normally you would klick on the Button "Open your Teams app" to proceede to open the Meeting in the local installed Microsoft Teams Application.

*Figure: Microsoft Teams Open Meeting Screen*

Nothing visual happens, which is frustration! If you are more experienced, you will find this error message in the Safari Console log: `Ignoring request to load this main resource because it has a custom protocol and comes from a sandboxed iframe`

## The Problem

*Figure: Safari Console Error Message*

Since Safari Version 15.4 (came with macOS 12.3) the browser follows new security rules which blocks external links in sandboxed iframes. There is a flag to allow this, but Microsoft has not set this flag for the relevant iframe.
Currently it still works with Chrome but this will [change soon](https://chromestatus.com/feature/5680742077038592) as they will activate this too.

> The Problem was fixed with Safari Version 15.5

## How To Fix?

> The simple fix would be, if Microsoft adds the flag but until this happens there are workarounds:

### A) Use Chrome

Use Chrome, but you need to open the invitatio link which opens the screen to select the way you join a meeting. There is no link on the button which fails which can be copied!

### B) Switch to Safari Responsive Design Mode

1. Activate the Developer Menu in Safari
   Safari > Preferences, click Advanced, then select `Show Develop menu in menu bar.`

   ::figure[Safari Preferences: Show Develop menu]{src="./safari-prefs-developer-menu.png" alt="Safari Preferences: Show Develop menu" width="100%"}

2. Switch to Mode "Responsive Design"
   Safari > Develop > `Enter Responsive Design Mode`

   ::figure[Safari Develop menu: Enter Responsive Design Mode]{src="./safari-developer-menu-responsive-design.png" alt="Safari Develop menu: Enter Responsive Design Mode" width="100%"}

3. Choose iPhone and reload the page

   ::figure[Responsive Design Mode: choose iPhone and reload]{src="./safari-responsive-iphone-reload.png" alt="Responsive Design Mode: choose iPhone and reload" width="100%"}

   > Without the **page reload** the link is still broken!

4. Click on the button "Open your Teams app"

   ::figure[Microsoft Teams mobile page: Open your Teams app]{src="./ms-teams-mobile-open-app.png" alt="Microsoft Teams mobile page: Open your Teams app" width="100%"}

[Write a response on Medium](https://andreasheissenberger.medium.com/microsoft-teams-app-fails-to-open-from-safari-1450608119be?responsesOpen=true)