When I’m trying to navigate scene view I can’t seem to get the view to go forward or backward. The up and down arrow keys seem to act like the hand tool dragging the view up and down. When I try to use “flythrough” the w and s keys don’t move the camera at all, but when I press w, the objects in the scene start to disappear. Then they start to come back when I press the s key. It’s like the program is rendering the environment as if my camera were moving and isn’t bothering to display objects that would be behind me, but my view just stays in the same place.
I’ve just started using Unity and the first time I used it, just messing around, I don’t think this was a problem. I’m using a laptop with a two-button trackpad. Please help!
I uninstalled and re-installed and it’s still like that. Is this how it’s supposed to be?
I had the same problem and its occur, after I place a terrain object, it has to do with the dimensions, can anyone help us here?
Found the solution, thanks for nothing 
Would you please post the solution you found?
I’m also new to Unity, had the same problem and this thread was the first to show up in a google search.
Thanks
The issue for me was that I had the Scene Gizmo locked to a specific axis; once I clicked the box in the center and changed to perspective, I was able to navigate the scene properly.
After reading the documentation, I realized I was in Isometric Mode, and attempting to move forward and reverse caused the issues described in Pendla10’s original post. Make sure you’re in perspective mode before attempting to move forward and reverse.
Ok I came across this as I had a similar problem and much to my embarrassment I realise my mistake. It happened to me after I added a terrain: the terrain is so large that your movement initially becomes unperceivable. Hold down the keys and have some patience.
I’m a noob and proud!