>Hi Viv, played around with Linqtoexcel and it's good for basic stuff but it doesn't support grouping which is a bummer but I can see it's uses in some scenarios, it basically dynamically builds a connection string based on your filename and creates an OledbConnection object and executes a query

Thanks for that. Will you continue to use it ?
At the moment my only requirement is creating XLS workbooks from data in a MongoDB database - no real need to go in the other direction - so I can do all I need with NPOI.....