I have a missing photos problem that doesn't seem related to moving or renaming the image files or folders. All my photos are saved on an external drive. When I enter the Develop module for any image in my catalog, I get the "file cannot be found" message. However, in the Library module, nothing appears to be amiss. There are no "file is missing" icons (e.g. exclamations, questions marks, etc).
Looking at the file structure in Lightroom, nothing looks out of the ordinary either. The external hard drive appears as "read" with a green rectangle next to the name. The folders and subfolders are not greyed out or have any warning icons. When I right-click on a subfolder and select "show in Finder", the folder pops up with no issues.
In addition to not being able to enter the Develop Module for existing images in my catalog, I cannot see any files on my external drive in the "Import" dialog box. I can see the external drive, but no folders or files.
These problems appeared suddenly after not having used Lightroom for a few months. I'm using macOS Monterey. Any help is appreciated!