HOW TO STOP HACKERS FROM INVADING YOUR NETWORK. Unethical hackers are always looking for weaker points in a network system to hack the security system of your company and get a hold of confidential and new information. Some "black-hat hackers" derive a vicarious pleasure from wreaking havoc on security systems and some hackers do it for money. Whatever the reason, malicious hackers are giving nightmares to companies and organizations of almost all sizes. Large corporate houses, banks, financial institutions, security establishments are particularly favorite targets for hackers. However, this menace can be prevented to a great extent if proper security measures are taken at the right time. 1 Follow forums. It is always a good idea to follow hacking forums as you will be able to pick up on all the latest methods being used. A good ethical hacking forum can be found at http://zerosecurity.org 2 Change default passwords immediately. Some