Complex sentence: HICOM's VMS system was open to anybody who wanted an account and as well as being famous for being the only machine that the hacker Kevin Mitnick ever had a legitimate account on it was also the first public access Internet Service Provider in the UK.
Split into simpler sentences: HICOM's VMS system was open to anybody who wanted an account and as well as being famous for being the only machine that the hacker Kevin Mitnick ever had a legitimate account on. It was also the first public access Internet Service Provider in the UK.