Without writing and distributing scripts that execute at system startup to create files based on the version of Mac OS X, and then checking for the existence of those files with Host Checker, one way to ensure certain versions of the OS is simply to calculate MD5 hashes of the /mach_kernel file. Of course, you'll have to update these hashes each time a new release comes out, but you can then create a single rule requiring the existence of /mach_kernel and a list of allowable MD5 hashes which works pretty well as a version checker. And BTW- does anyone else think it might be a good idea for Host Checker to be able to execute a command and test the results? Message Edited by David_Bailey on 09-21-2009 10:14 AM ... View more