Does this message pop up for every document you are working at or only to a specific one?
What's your operating system?
Note: You are seeing a new feature with InDesign 16.0.1 described here:
Detect damaged documents and recover You can save time in troubleshooting the damaged documents. InDesign detects the damaged documents and try to repair them on Adobe servers. When you open a document, if the document is damaged, a prompt appears to choose to repair the document.