auto highlighting of cells when clicked on

[Guest]

i've managed to turn on something that not only highlights an area but
creates a box around it also when i click on any cell in my worksheet.
please help someone how do i turn this off and how did i turn it on so i
won't do it again.

thank you

 

[Guest]

sounds like EXT mode (should say EXT at the bottom of the window)

touch F8 to fix