Xbox 360 currently uses Hitachi -LG GDR-3 120L, Toshiba and Samsung TS-H943 DVD drives. At the same time, all Xbox 360 executable files (XEX files) are digitally signed by Microsoft (only Microsoft has a private key), so if the cracker starts on the XEX file, the digital signature will be changed, so the XEX file cannot be started. In addition, in order to prevent XEX files from being started from DVD-R or other recording media, Microsoft added a so-called "Mediaflag" to each XEX file, which told Xbox 360 what recording media (CD-R, DVD-R, DVD+R, DVD-RW, HDD, DVD Xbox, DVD Xbox 360) can be started. If the Mediaflag is changed, it will also destroy the XEX file.