Reading word document giving error in aps.net

Question

i am trying to read a work microsoft 2010 word document in asp.net, it works fine in local host i mean when i debug application, but when i host it in iis gives errorError
Error: KushL7DocParser / Message :Object reference not set to an instance of an object. / Data :System.Collections.ListDictionaryInternal / Exception:  / Target: Void btnPreview_Click(System.Object, System.EventArgs)


please help me
Thanks