Can anyone tell what is the problem with this command?

Henry Chan:
can anyone tell what is the problem with this command?

Aaron Lockhart:
Have you tried using \; as the command delimiter instead of +?

Henry Chan:
\; works this time. Sometimes + works but not \; , wired.

Alistair Mackay:
Also worth quoting {} as in

... -exec mv "{}" /opt/foundfiles \;

Aaron Lockhart:
That’s true, and will help ensure that the results are all correctly captured after shell expansion.