I'm having an issue where excel will not allow me to use ctrl-shift-arrow to maneuver about ranges.

for example if i wanted to enter a sumproduct formula i'd choose the column header, press ctrl-shift-down arrow, and the column would highlight.

For some reason when I do that now it exits my formula input and tells me my formula is no good.

Oddly enough pressing shift-ctrl-down arrow does work, but feels very unnatural to me.

Originally I thought I had a macro or something assigned to ctrl-shift-arrow but no matter which arrow i press i get the same error. so what setting did I screw up and how do I fix it?

thanks,
mark