Teams add in Greyed out in Outlook.

Hi Chris Holgate

Welcome to Microsoft Q&A forum 

To help me find the root cause why the Classic Outlook do not let you schedule a Teams meeting, could you please clarify a few details: 

1.Which version of Outlook are you using? (Desktop app, Web, or Mobile) 

2.Is Teams installed as a desktop app or are you using the web version? 

3.Are both apps updated to the latest version? 

4.Is this issue affecting other users in your organization or just you? 

5.Please check one more time to make sure you are sign in both Outlook and Teams with the same account 

In the meantime, please try some initial troubleshooting steps: 

1.Check the Teams Add-in in Outlook 

-In Outlook, go to File > Options > Add-ins 

-At the bottom, select COM Add-ins > Go. 

-Ensure Microsoft Teams Meeting Add-in for Microsoft Office is checked.  

-If unchecked, enable it and restart Outlook. 

-If it’s missing, reinstall Teams or Office. 

2.Clear Teams Cache 

-If Teams is still running, right-click the Teams icon on the taskbar, and then select Quit. 

-Open the Run dialog box by pressing the Windows logo key  +R. 

-In the Run dialog box, enter %userprofile%\appdata\local\Packages\MSTeams_8wekyb3d8bbwe\LocalCache\Microsoft\MSTeams 

-Select OK. 

-Delete all files and folders in the directory. 

-Restart Teams. 

3.Troubleshooting (automated steps) 

-Use the classic Teams add-in for classic Outlook troubleshooter to install the classic Teams add-in for  

classic Outlook. 

-Open sarahome 

-Click Open if you get a pop-up window indicating This site is trying to open Get Help. 

-Follow the steps in the Get Help window. 

4.Troubleshooting (manual steps) 

-Sign out of Teams and then restart it. (In the search box on the taskbar, type Teams, and then select it from the results.) 

-Close Outlook and then restart it. (In the search box on the taskbar, type Outlook, and then select it from the results.) 

(Reference Troubleshoot the Teams Meeting add-in in Outlook for Windows - Microsoft ) 

Additionally, you can seek assistance from your IT admin. For further troubleshooting steps they can perform, please visit Resolve issues with Teams Meeting add-in for classic Outlook - Microsoft Teams | Microsoft Learn 

Note: If you’re unsure who the IT Admin is within your organization, you can find guidance on locating them here: How do I find my Microsoft 365 admin? - Microsoft Support.     

The initial response may not fully address your needs, but it will help me better understand your situation and try to find the root causes. Thank you for your patience while we work through it   

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