The tour shows up in the history but cannot be opened/viewed. It also won't get synced to Garmin Connect.
Also look to NewFiles folder. Try to check last few files from Activities folder.
Have you tried to look at the files via www.fitfileviewer.com?
This can happen.
Where did you find this file?
You can also try to put it manually to NewFiles folder, Edge should sync it automatically then after a while.
If not, put it to Activities folder, I have done that once with my watches in the past and it worked well.
Also, there is this tool www.fitfilerepairtool.info, but I haven't tried it yet.