Read Import file in UserControl

hi,

I am using an UserControl to read Imported Excel, CSV files using with DataGrid..

i have alreay done to read and save the import files in aspx page...but it gives an error on UserControl..

Object refrence is not set... and ex = {"The Microsoft Jet database engine cannot open the file 'C:\\Inetpub\\wwwroot\\...\Files\\'.  It is already opened exclusively by another user, or you need permission to view its data."}

help me ..ASAP