What is the ruling on working for a company that sends advertisements for products and services (a mixture of permissible and impermissible) via email, if the inquirer's role is limited to technical support (IT) for sending these advertisements, and is he considered sinful, and what is the ruling on the money earned?

It is forbidden to work for a company where there is direct assistance to what is unlawful (haram), such as someone who works in maintaining servers that are used by those who market both lawful (halal) and unlawful things; this is based on the Almighty's saying: "And cooperate in righteousness and piety, but do not cooperate in sin and aggression. And fear Allah; indeed, Allah is severe in penalty." As for money taken before knowledge of its prohibition, there is no harm in benefiting from it. However, whatever was taken after knowledge of its prohibition and not spent must be disposed of through charity for good causes, unless there is a need for it, in which case one may take what is needed and donate the rest.