During the past 10 years, I have used 4 laptops to save files (pdf) to USB. Now on my current 4th laptop, I am unable to open, copy or attach files saved in USB through earlier laptops. Getting message>Error 0x8071771. I also tried>Select File > Properties > Advanced > remove the check mark from Encrypt contents to secure data > got the message "Error occurred applying attributes to the file". How do I open files & how do I avoid this issue in the future?