what is this strange behavior when I click in a cell in Excel 2010?

Question

I'm using Excel 2010 and I'm trying to edit dates in a column, but I notice that when I click in a cell, make no edits then hit enter, this strangeness occurs:

First, I click in the cell:

Then double click as if to edit...:

Then hit enter after no touchy poo...

Look at that! Now its some bizzare format I do not recognize. And wait, if I do the drop down undo button, this is what I see:

Does that shed any light? If it does, maybe it will help me actually successfully edit because when I do type something in there--even if it what was already there--it gives me this:

What exactly is going on here?

Answer 1

You'll most likely find that the cell isn't being formatted as a date correctly. Right click -> Format Cell choose the appropriate Date format and it should pop right back into being a date again (as Excel stores dates as numbers and then formats to suit)

Provided A29 isn't also a formula, drop the leading 0 (just for consistency, probably won't make a difference but you never know)