inserted between tabs 54 and 56 see fig1 this increases the overall cohesive bond between the locking disk 20 and bezel 42 thus the bezel flanges prevent someone from jimmying the bezel in an attempt to disengage lever 64 from engagement member 32 as explained above when the computer operating system is turned on it first attempts to read data from any external disk drive that contains a disk this is done before attempting to boot off any internal hard disk while locking disk 20 is locked into the disk drive the computer system thinks a floppy disk resides in its disk drive therefore the computer tries to read the locking disk because the locking disk cannot be read the computer operating system acknowledges a reading error condition and discontinues any further part of the boot routine the locking disk holes 22 and 24 are positioned to prevent any part of the disk drive recording playback head and the disk spindle from contacting the locking disk this prevents the disk drive from being damaged when the computer system is turned on while the lockout device is engaged any additional slots or holes required by a particular disk drive locking mechanism are incorporated into the locking disk for example notch 30 in the 51 4 34 locking disk 20 of fig1 and notches 80 and hole 78 in the 31 2 34 locking disk in fig2 the locking disk is made out.