May i know what is the error message that you are getting when you try to edit the images.
I don't have any quick collections. How did all 17,000 of my photos get in a quick collection that I don't have because I have cleared them all. My develop screen is blank when I change from the library module to the develop module. I can't edit any photos.
The presence of the grey dot may or may not be related to your issues with editing. Troubleshooting steps:
1. Disable LR's use of the graphics processor by unchecking the option Preferences > Performance > Use Graphics Processor. If that doesn't address the editing issue, then:
2. Post a full-resolution screenshot of your LR window in Library mode with the filmstrip open and the left-hand Catalog panel visible (where it lists All Photographs, Quick Collection, etc.).
3. Post a full-resolution screenshot of your LR window in Develop mode showing with a "blank" image showing.
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Thank you to everyone. I restarted lightroom and the problem went away.