numbers won't add

[esoxlucieus]

I know, this is pretty darn basic. So be it. I've been sent a spread sheet and I want to add some of the columns. Neither a formula add them, using the 'sum' sign, or the auto sum (from the bottom right hand corner). I have gone back into 'Format', 'cells' and made sure that the columns are listed as 'numbers'. Suggestions?

[MDubbelboer]

I know, this is pretty darn basic. So be it. I've been sent a spread sheet and I want to add some of the columns. Neither a formula add them, using the 'sum' sign, or the auto sum (from the bottom right hand corner). I have gone back into 'Format', 'cells' and made sure that the columns are listed as 'numbers'. Suggestions?

in a general format cell use the formula
=value(trim(cell))
see if that converts it. you might have some funny formatting forcing it as text even though you specify the number format