Hello Pierre Auger,
Even if the user is part of the local administrators group, it doesn't necessarily grant them the required permissions to run scheduled tasks. You need to ensure that the user has the necessary permissions to execute the task. To check this, right-click on the task in the Task Scheduler, select "Properties," and go to the "General" tab. Make sure the user account has "Run with highest privileges" selected.
On some systems, users may need to have the "Log on as a batch job" right to run scheduled tasks. Check your local security policy or group policy to ensure the user has this right. To do this, open the Local Security Policy editor (secpol.msc), navigate to "Local Policies" > "User Rights Assignment," and verify if the user or a group they belong to has the "Log on as a batch job" right.
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