I got only 1 disk of 500GB in my lappy...i want to install windows 10 on it...but it is saying that i need to convert MBR disk to GPT...i deleted all my partitions and made it into one 500GB partition. ..but still if i rigjt click on the disk in disk management the "convert to GPT" option is not ebabled...i tried through cmd prompt also...got no idea what to do...current OS installed is windows 8...pls help