I booted my machine this morning ( win 8 64 bit pro ) , fired up outlook and my folder pane is minimised to the right hand side of the screen.

If i click on a folder it shows the contents, however if i use the expand  ( > ) on the top of the folder pane, the folders are briefly displayed before disappearing and i am left with a blank folder pane

how can i get back top showing all folder in the folder