If you install the IIe Card software and properly configure everything, then click on IIe Startup icon, it will go to IIe mode and then check the boot devices for a suitable startup device.
In order to boot to ProDOS in the IIe mode, double-click the BASIC.SYSTEM icon, unless you have a ProDOS or DOS 3.3 disk you want to boot to. This will launch you directly into ProDOS.
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