Customer has added drivers that are no longer needed in their preboot and tthere isn't an error.
There isn't a way to remove the drivers through the UI.
Open File Explorer
Go to <drive>:\Program Files\Altiris\Deployment\BDC\bootwiz\Platforms\WinPE\<arch>\Drivers\CUSTOM\Drivers
Delete the folder that contains the drivers that are no longer needed
Navigate to Settings > All Settings > Deployment > Packages > Click on 'BDC' then click 'Update Distribution Points'. This will remove the reference to the driver for package servers and update the BDC package
Rebuild any Preboot Configurations that need the driver removed