Hello,
You can use powershell:
Enumerate your printers and see their paper sizes
Get-Printer | Get-PrintConfiguration | foreach-object { Write-Host $.PrinterName: $.PaperSize }
Update the paper size for your printer
Set-PrintConfiguration -PrinterName "Your Printer Name" -PaperSize "A4"
You could test it on one of your machines, and if successful, employ a boot script or Task Scheduler to deploy it across all machines.
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