Schedule report failed .

Hello All,

Our user is scheduled the webi intelligence report and selected the format as "Adobe Acrobat" and destination as Mail.
After scheduling the report the status is Failed and it was throwing an error "while trying to invoke the method com.businessobjects.sdk.core.server.IServer.getServerContext() of an object returned from com.businessobjects.rebean.wi.impl.services.DocumentInstanceManagementServiceImpl.getServer(com.businessobjects.sdk.core.context.IContext, com.businessobjects.rebean.wi.model.engine.IDocumentInstance)"

Environment
Business Objects 4.0 sp4
Windows 2008