I was having similar issues to a lot of people where the hand tool would not work when I use the spacebar to quickly swap from whatever tool I am currently using. The issue results in the hand appearing and not being able to "grab" onto the page and pan around the artboard.
I haven't had luck using any of the methods listed in all of the forums that I've checked, however in doing some experimenting I've found that I am able to initiate the "grabbing" of the page by using SPACE in conjunction with CTRL.
Holding SPACE + CTRL will bring up the zoom function.
Holding SPACE and clicking CTRL allows for the hand tool to move around only while maintaining the hold on the SPACE bar.
Releasing the SPACE bar and clicking it again results in the hand tool being unable to function properly.