The hardening, called also ‘hardening’ of the computer, in the world of computer experts means tips and tricks for hardening the software system as much as the security measures as increasing attacks by hackers to make very difficult or virtually impossible. There are various measures, so to harden the computer system of the online shops, that the own shop is secured, both the data of customers from outside access is protected. More information is housed here: Royal Dutch Shell. Another definition for the computer-hardening is the Federal Office for security in information technology. According to them, there is hardening a server or computer system in the deletion of all computer functions and all unnecessary software components that a user does not need to perform the desired task. The operation of the system will be backed up while the security aspect is guaranteed. So, the possibility of external attacks can be minimized. Online shops that take these safety aspects especially seriously, can even a get certified seal, which verified the computer hardening them. This protection by hardening it aims, that system of online stores to set up so that it easily by many, on their trust unverified persons can be used. To implement tips and tricks for hardening of the system to the computer-hardening specifically for its own computer system of the online shops, various tips and rules should be adhered, that can significantly increase the safety factor. The operator should consider first and foremost, as the possibilities for the use of its computer system can reduce down to zero. Each system revealed his particular vulnerabilities, which should then immediately be removed during the operation. This significantly reduces the different methods of attack by hackers or computer savvy cheaters. The attack on the operating system not be prevented, the next measure of the Defense be so far, the attacker the number of usable tools of the online shop just how reduce.