Ctrl+Tab hotkey combination not working.

I’m new to Blender and running into a strange problem. When I try to use the hotkey combination (ctrl+tab) to access the selection type window (where you choose face/vector/edge), it just switches between windows a la Alt-Tab.

The strange thing is if I re-install, the problem goes away… until I create a new file. The problem just pops right back.

It’s not a terrible issue… but I need to work fast to meet deadlines and this function saves a LOT of time.

Anyone know what’s going on? Thanks.

Check preferences, perhaps?

No clue if that can affect it.