which actions can't you undo in excel?

[NYears]

Sometimes when using excel and I alter a formula, then change my mind and
click undo, it doesn't undo the last action, but one several actions back.

I realise there are some actions you can't undo, such as deleting a
worksheet, which you are warned about when you are about to do it.
If anyone knows of a list of other actions which can't be reveresed by using
the undo command I'd be grateful.

 

[Richard O. Neville]

If you have AutoSave turned on to save every five minutes or so, it is
possible for you to complete an action in a cell. Then you decide to undo
it, but in the meantime AutoSave has done its work. Then your last action
could not be undone by the Undo command. Check your setting in
Tools-Options, Save tab. I don't know why Undo would affect an action
several actions back.

 

[Dave Peterson]

I've never seen excel go out of order in the Undo's.

Are you sure you're seeing that?

And just to add to Richard's response--most macros kill the undo stack, too.
This includes worksheet/workbook events, too.