@softraid-support OK I figured it out!!! The files I was trying to move to the Thunder Bay drive were from Google Drive. The folders I was t...

Also Thunder Bay shows as Not Case Sensitive.

I looked in Disk Utility and it says my Macintosh HD is not case sensitive.

My source Volume is formatted as APFS

@softraid-support My source volume is just my Macintosh HD that shipped with my Mac. I'm not using Time Machine. I use a 3rd party service to backup...

@softraid-support I thought I did, but that worked, thank you very much!

I was having the same issue on 10.14.5 on an iMac Pro this morning. The Security Settings fixed my issue. Thank you!