Question Summary:
Is it permissible to use advertising of halal products and services on a website that is meant for dissemination of knowledge about Islam?

Question Detail:

Is it permissible to use advertising of halal products and services on a website that is meant for dissemination of knowledge about Islam?

Answer :

In the name of Allah, Most Gracious, Most Merciful
Assalaamu `alaykum waRahmatullahi Wabarakatoh
Kindly elaborate on the words “that is meant…” Was there any conditions at the time of setting the website? Nevertheless, in principle, it is permissible to advertise halal products and services on websites disseminating knowledge on Islam. 
And Allah knows best
Wassalam
Mufti Ebrahim Desai
Darul Iftaa, Madrassah In'aamiyyah