As pointed out, both are used more or less synonymously, so never trust that the user ment the same thing you do.

Additional to the "you physically can´t / you are nto allowed to" meaning, there are some additional hints:

"Kein Zutritt" is mostly used for closed spaces (i.e. buildings) while "Kein Zugang" could also describe an open place, e.g. a garden or park.

While "Kein Zutritt" always means "you are not allowed to enter" and describes the object you might wish to enter, "kein Zugang" could describe the access path or way ahead of you. It could mean "this way will not lead to the building, please use the next one further left.

As pointed out, both are used more or less synonymously, so never trust that the user meant the same thing you do.

Additional to the "you physically can´t / you aren´t allowed to" meaning, there are some additional hints:

"Kein Zutritt" is mostly used for closed spaces (i.e. buildings) while "Kein Zugang" could also describe an open place, e.g. a garden or park.

While "Kein Zutritt" always means "You are not allowed to enter." and describes the object you might wish to enter, "kein Zugang" could describe the access path or way ahead of you. It could mean "This way will not lead to the building, please use the next one further left.".