To provide a secure installation and execution software environment, locked version numbers are maintained. A locked version number associated with a software program may be stored. When a request is received to update the software program with an update package, a package number of the update package may be compared to the locked version number. The software program may be updated with the update package if the package number is at least as recent as the locked version number, and the updating of the software program with the update package may be restricted if the package number is earlier than the locked version number.