do not open email attachment from "fed ex"
Got email saying "trouble delivering" from "fed ex"...said to open attachment "label???something) I made mistake of doing so and message said I had no access to anything on my computer until I paid a certain amount of bitcoins to unlock it. All files had a suffix I didn't recognize, that if I tried to open them sent me to box saying "cannot open, search internet for program to do so".
To solve problem I ran restore program (entered "restore" in search on my windows 10 computer) to a week earlier when last major MS update was done. Lost anything since then, but everything's working now.