Error while installing Business Analytics in Nav 4.0 Sp3 on windows 2003 server(R2)SP2

I am trying to install BA on Nav4.0 SP3. I copied the files Common,configurator in a new folder c://program files/microsoft business solutions-navision/BA But at the first step only it is giving the errror. Request you to kindly give me any solutions for the peroblem as it is very urgent at the client place. ERROR : Index and length must refer to a location within the string Parameter name :Length