Various causes: There are very many causes, from congestive heart failure, to lymphedema, to venous insufficiency, blood clots, pregnancy, a various other causes, including serious and not-so-serious causes.
I have a Sony DVP ns55p blu-ray player with a usb port in the front. The player requires that the usb flash device (thumb drive) be formatted in FAT32in order to recognize it.
Well, laptops with an inner Blu-Ray disc drive can directly play Blu-Ray discs. And every laotops can play Blu-Ray discs as long as you have a external Blu-Ray player and a blu-ray player software, put your Blu-Rays in the player and then connect it to your laptop with USB drive, you can successfully play Blu-Rays.