Hello Henry. I'm Greg, here to help you with this.
You can run Recuva on the File History drive to see what it finds: http://www.piriform.com/recuva/features
Are you sure all the locations you selected were being backed up. Choose the locations for File History to back up:
https://www.zdnet.com/home-and-office/work-life...
But I do not recommend File History due to number of files I've seen lost. It especially has a problem when connecting it to a new PC to transfer files, and will wipe out the entire archive because it thinks you're setting up a new one instead - unless you follow these exact steps:
https://www.techrepublic.com/article/how-to-cor...
Here are easy, free (or cheap) ways to have a mult-layered backup so you never lose files: https://answers.microsoft.com/en-us/windows/for...
Feel free to ask back any questions. Based on the results you post back, I will have other suggestions if necessary.
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