blocked site

Ok I will ask again with more detail I went to St. Pius Church (pius.org) to read the church bulletin and it was blocked i tried a couple of things to manage the permission but they have not worked. I am new to Firefox. I have concerns that it i go to one of my professional sites t register for a seminar or to download a document that this will happen there and I donot want to deal with it. What would be helpful is to know how to prevent this from happening in the future. So in general if i go to a site (ie pius.org) and want to read the document I do not want to be blocked I need information to avoid this Thank you. I hope that this time i am clear I thought last time i was clear but obviously i was not