My 2 4TB Sandisk external drives will not show up for Dropbox Backup. My 2TB Sandisk external drive does. The only difference between them is that the 2TB is APFS Case Sensitive and the 4TB drives are just APFS.
I have tried the option key in Accounts and pressed the Reset Operating System Warnings many times. It does not say that it does anything like the other two options do.
I am running the latest Mac OS and have updated Dropbox.
Any help would be appreciated