Howard and Shikha
I figured out why my old microSD card died on me.  When I plugged in my old Android phone at work, the antivirus software of my laptop wanted to scan the whole thing every time.  I was plugging it in to charge it, but the constant reads wore out the flash.  My new Android phone mounts as a CD drive (instead of the entire thing). I can only see the phone if I unmount my CD drive.  This is perfect for charging at work now.  Be careful with virus scanners if you have an Android phone that auto mounts your entire phone's Micro SD!