Omeka S Error: TypeError SplFileInfo::__construct(): Argument #1 ($filename) must be of type string, bool given

Greetings,

I get the following error for Omeka S when I try to edit an Item:

TypeError
SplFileInfo::__construct(): Argument #1 ($filename) must be of type string, bool given

This error followed an upgrade to Omeka S 4.0

Thank you,
Doug