Exactly what it says in the title. Whenever I open hammer there is only one viewport that takes up the whole screen.

I've tried everything possible. I've even restarted steam but that does not seem to work.

Update: After restarting a couple of times CTRL + A somehow fixed it.

In registry:
HKEY_CURRENT_USER\Software\Valve\Hammer\Splitter
Save this registry "directory" so if it happens again, you can restore it
SplitterHeight and SplitterWidth is the position of the split, setting both to 100 can reveal them and then can be dragged (for me its 446 and 761), My WindowPlacement key is: (-4 -23) (-1 -1) (652 22 1428 22) 3