Is it permissible to use the university's printer and paper to print personal materials for students or relatives, or religious materials unrelated to work, and what is the ruling on printing for professors and students given their affiliation with the university?

It is not permissible to use the workplace printer for personal purposes or to print papers unrelated to work interests, whether religious or otherwise. This is because it constitutes a breach of trust, in accordance with the Almighty's saying: "O you who have believed, do not betray Allah and the Messenger or betray your trusts while you know." However, it is permissible if the university or institution grants permission, or if it is common practice without objection, as what is recognized by custom is like what is stipulated by a condition.