While you may have removed the columns from your displayed report – I bet the columns are still in the data provider. If you use “Export” from Data Manager – it is exporting the data provider, not the formatted report.
If you can, remove the columns from the query panel, so that the query panel returns the columns you want to export.
If that doesn’t work for you, then use one of the other ways to get data into Excel. Here are some alternatives from our Reporter FAQ.
Anita Craig 
(BOB member since 2002-06-17)