First question: does an easement exist at all?
“Neighbor blocking my driveway” is the most-searched easement situation, and the answer always starts with the same question: is there an easement, and how did it arise? A driveway that crosses a neighbor's land could rest on a recorded express easement (check your deed and title commitment), an implied easement created when the parcels were split, or a prescriptive easement earned by long, open, non-permissive use.
If a recorded easement exists, the neighbor generally cannot block it, and the recorded instrument controls the scope. If no easement is recorded, the analysis shifts to whether one can be implied or claimed by prescription — which is fact-specific and state-specific.
If the driveway is on a recorded easement
Pull the recorded easement document — not just the title-commitment exception line. It will define who benefits, where the easement runs, and what it allows. Blocking a validly recorded access easement is usually actionable; the typical procedural path is a demand letter followed, if necessary, by a quiet-title or declaratory-judgment action.
If there is no recorded easement
Then the question becomes whether the use can be implied (from the history of the parcel split) or claimed by prescription (from long, adverse use). Prescription depends entirely on your state's statutory period and elements — open, notorious, continuous, and adverse use for the full period. Run the dispute-pathway map for your state to see which doctrine fits and what the period is.