Hello,

Somehow I'm no longer able to open Zotero app on my MacBook.
I have this error message that "A copy of Zotero is already open. Only one copy of Zotero can be open at a time.", although I didn't open it.
What should I do? I'm heavily relying on the references on Zotero so I must be able to use my library.

Thanks,
Haerin