Dude... That was me. j/k No system is 100% secure. Every system is hackable. But to hack you do not say. Pssst. Tell me how to do this. Nah Ahh. What you do is study your ass off.
Learn first how email works. Read up on SMTP, POP3, iMap etc etc etc.
Next read up on ways to secure a web server and the flaws each of those have if any. Next what scripting languages is said target using? Are there any holes in its implementation of a standard?
Next what OS is the server you want access to using? Windows, crap you will never break into that. It is the most secure... Ohh wait
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