Saved from a previous post...
Excel likes to help.
Try this on a test worksheet.
Select A1 and hit ctrl-; (to put the date in the cell)
now select B1 and type: =a1
Notice that excel changed the format of B1 to match the format in A1.
Now format D1 as Text.
put ASDF in D1
put =D1 in E1
You see ASDF.
With E1 selected, hit the F2 key and then enter (to pretend that you're changing
Excel has "helped" you by changing that cell's format to text.
I don't know of any way of changing this behavior.
I just select the cell, and reformat it to General (or whatever I wanted). I
hit F2 and then enter (to reenter that formula).
Sometimes this feature is nice, sometimes it ain't.