Error generated after moving the catalog location

[treyneal]

In an effort to reduce the space taken on my local drive I moved my catalog to a different attached drive (Promise Pegasus).  Plus failed to find it as expected so I selected
Catalog Management > Locate Existing Catalog 
Entered the new location on the attached drive.
Plus notified me that I needed to reindex as this move was executed after I downloaded and installed the latest beta (build 4073).
This produced a runtime error - open_catalog failed: "open_catalog: RuntimeError/existing catalog not found:\"/ and then the path to the original location"

macOS Sierra v10.12.6

[treyneal]

A little more detail -
Moved the catalog back to its original location
Plus notified to re-index
Followed the procedure for re-index.
Catalog re-indexing began without error, however the Maintenance window is now showing the path to the attached drive although it is re-indexing.

[Soizic]

a click on "Locate existing catalog" seems suffisant for a new dress

[treyneal]

a click on "Locate existing catalog" seems suffisant for a new dress

As I mentioned in the OP, I selected "Locate existing catalog" as the first step after the move.  That was the step just prior to the error message being generated.

[treyneal]

Further information on the error process.

Re-indexing appears to have completed without an error.
Had to Reintegrate Forgotten Catalog under Maintenance to get the thumbnails to appear again.

I will create a separate, small catalog and attempt to reproduce the error.