Old thriller we can’t remember the name!

An author is hired to write a book. He is in an old White ‘Haunted’ House writing when he starts having encounters with ghosts. In the end you find all the encounters were just his story they didn’t really happen.

Sounds like Deadline (2009)

How old is it? Possibly House of the Long Shadows?

It’s old…probably 80s. Similar to House. But it’s not it.