Under the View Tab, I clicked Arrange All which split my open document into side by side panels. The 1st panel was page one of the document and the 2nd panel was the second page of the document.

I am unable to undo the effects of Arrange All. Opening document will again tile the panels side by side as long as the Word window is wide enough.

The "solution" Macropod put all over the internet ~2007 was to close Word, open it and maximize the window. This is totally wrong - maximizing the Word window puts the document in side by side view again.

Win7 Ultimate, Office 2010, 32 bit.