If you are using a 64bit version of windows, and are using the Jet OLE DB driver in the ADODB datalinq, then in the windows registry edit this key
[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\ Jet\4.0\Engines\Excel]
and set TypeGuessRows = 0
If you are on a 32bit windows the key is probably called:[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\ Jet\4.0\Engines\Excel]
The reason for this is that the Excel database driver (not XPression, but excel itself), looks are the first few rows in a column and tries to determine what data type is contained in that column. So if the first few rows are all text is assumes everything should be text and not numbers, etc. It does not use the cell format defined in excel for this.
Setting that registry key to zero will force excel to look at the entire column and not just the first few rows before it decides on the data type.
#XPression