Hi, I'm having trouble with one of his quests, it says I should head towards Solitude, but if there is meant to be an event or so, it is not triggering
If you're talking about Night of the Hunter, head back from the docks up towards the gate. He's leaning against the wall.
You need to actually walk up the path to trigger the forcegreet. If he's not there, chances are you have a town expansion or something that's placed a mesh when there's meant to be clear ground there.