How can I deploy a custom Teams background company-wide without Teams Premium?

For the classic Teams client, the image needs to be copied into the user's Teams upload folder. You generally need two files: the full-size image named with a GUID and a thumbnail using the same GUID followed by `_thumb`. The usual path is `%localappdata%PackagesMSTeams_8wekyb3d8bbweLocalCacheMicrosoftMSTeamsBackgroundsUploads`. The deployment must run in the user's context, not as SYSTEM, so Active Setup or another per-user mechanism may be needed. Be aware that Microsoft can change this path between client versions.

A successful Win32 deployment only confirms that the script ran or the files were copied. It does not mean Teams recognized them. The newer Teams client and the classic client use different package locations, so verify which client is installed and copy the files to the matching per-user directory. This method adds the image to the picker but does not make it the default background.

A practical no-cost approach is to deploy the image and thumbnail with PowerShell, then give users instructions to open the background effects menu and select it themselves. There is no supported way to force a company-wide default background without the relevant premium capability.