access to photos from and external drive

I have a MBP and I have my iTunes library and my photos library on an external drive. I am able to get my iTunes library to show up and can see the songs. But for whatever reason, the images tab shows an iPhoto library and has a red “!” indicating that it is missing. I am able to open the Apple photos app and it shows the photos with no problem. I have set the proper photos library to the location of the file on the external drive in the preferences in photos. I see that there is a preferences in FM 5 that has a libraries tab and shows “load photos library” and “load iPhoto library”. the iPhoto library shows up with the red “!”, but the photos library does not show up. Please help. Thanks, Bob.