Ideas-
1.reference Excel in your project references
2.in your sub that formats, use
With myExcel 'your Excel object
.selection.columnwidth = 15 'etc.
End With

the best way to do this part is to record it in Excel VBA, then cut and paste into your VB project. Once it is pasted, put the "." before the commands so VB knows you are talking about the Excel object.

If this still doesn't work, provide me with more details. I am assuming that you expect to have Excel on the end user's machine.