SE Plus Ver8.8 Can Not Access Negative Scan

[BruceNimmer]

When I select the icon for Positive, Kodachrome or Negative the only selection available to me in the drop down menu is Positive, the Kodachrome and Negative are grayed out and not able to be selected. I'm running Mac OS 10.12.6 using an Epson Perfection 4870 Photo scanner. All drivers have been updated. I'm trying to scan B&W negatives. Any idea why the selections are grayed out?

[LSI_Ketelhohn]

Dear user,

please make sure you have activated the transparency mode. Negative and Kodachrome are not available in reflective.
In case transparency is not available make sure your scanner's transparency unit is correctly connected.

Kind regards,
Arne