Excel 2007 : V Lookup not picking up 'table array' data

[Phil_Morgan]

Hi all

I am having some problems with VLookup's in Excel 2007.

When selecting the 'table array' it will not let me select data from a seperate workbook or sheet; only allowing me to use the data already in the sheet I am using the formula in?

I have a feeling that some of my settings may have been changed by accident, as this problem has only just come up.

Can anyone suggest what may be wrong or point me in the direction of re-setting the settings to default.

Thanks
Phil