Excel is trying to be helpful. Isn't that nice?
Formatting the cell to General won't work (as you've noticed). You must first format the cell (or row/column/range) as TEXT, then you can type in 5-1 and not have it change on you.
Or, if this data appears sporadically, you can bypass this behavior by putting a single quote/apostrophe in front of the text as you are entering it.
Type in [COLOR=blue white]'5-1[/color]. You will notice that only [COLOR=blue white]5-1[/color] is displayed: the apostrophe just tells excel that what comes next - no matter what it looks like - is text.
[tt]_____
[blue]-John[/blue][/tt]
[tab][red]The plural of anecdote is not data[/red]
Help us help you. Please read FAQ181-2886 before posting.