I know that Alt-F4 closes a program.
But when I tried CTRL-ALT-SHIFT-F4, the following msgbox popped up:

"Cannot open Microsoft Excel Add-In for editing. Please edit the source
document instead."

I tried to replicate what happened, and failed until I did the
following. First, have an unsaved workbook open. Then, press the
shortcut key. When the dialog prompts you to save, cancel. Then, press
the shortcut key again, and I get the above msgbox every time. What is
it doing?


Also, CTRL-SHIFT-F4 seems to activate the previous blank cell either
within a selection, or for the entire sheet if only a single cell is
selected. Can someone confirm that this is indeed what is going on?