Excel on MAC / Excel online

Make sure that have a Microsoft 365 subscription. Microsoft does not offer plug-in support for standalone Office for Mac purchases, such as Office for Mac 2019. You can check which version of Excel you have by navigating to File -> Account -> About Excel.
“Centralized Deployment” of Office add-ins requires that the user has a valid Exchange license, as listed here -> Determine if Centralized Deployment of add-ins works for your organization - Microsoft 365 admin | Microsoft Learn, so make sure you install the Artemis Sheets add-in locally and not for all users. After installation, the add-in must appear in the My Add-ins tab and not in Admin Managed tab.

One of the most successful troubleshooting tips we use for a variety of common issues is to refresh your Artemis Sheets Add-in. This will clear your cache, update new features and platform upgrades and make sure you have the latest, stable version running. Here are the steps to clear the cache:
- Go to Insert menu and click My Add-ins button
- Click the upper right corner Refresh button
- Click the Artemis Sheets add-in box (so it’s highlighted)
- Click the lower right corner Add button

If the above didn’t solve your issues, try to manually clear the Office cache.

On MAC this is done by deleting the contents of the below folders(s)
- /Users/{your_name_on_the_device}/Library/Containers/com.Microsoft.OsfWebHost/Data
- /Users/{your_name_on_the_device}/Library/Containers/com.microsoft.Excel/Data
On Windows delete the content of the folder %LOCALAPPDATA%\Microsoft\Office\16.0\Wef.
For Excel Online clear the browser cache.

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