It turned out the drive was failing. It took a lot of testing to discover that and it was a royal pain.
Let's see what others have reported.
Every couple of months my Win 10 machine won't boot and requires me to use a repair disk. Sometimes the repair works quickly and easily, other times it has to find an image.
My question is: why does happen every few months and what can I do to figure out what's happening?
This is not a computer that gets a lot of use, downloads etc and I use Norton Security, MalwareBytes and HitmanPro routinely.
Thanks,
Bob

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