Siebel server not starting after adapter installation


We have Siebel 6 installed on Windows NT Server. Oracle database on the same machine. The machine is not part of any domain. The server used to work fine.
Recently for integration, we installed webMethods Siebel adapter for Enterprise Server 4.1. We could do simple integrations where webMethods fetched data from Siebel. To trigger webMethods from Siebel, we created sample code as per the documentation. It requires to replace siebel.srf on the server for which we had to stop the service. Since then the service is not starting. We couldn’t replace the file, as it was not giving access to the sieble file either.
The service leaves following message in event viewer.
GEN-02009: (siebsvc.cpp 10: 205) error code = 2009, system error = 2009, msg1 = (null), msg2 = (null), msg3 = (null), msg4 = (null)
Siebel knowledgebase points to insufficient user rights, but the user has full authority of the machine.

Did anyone else faced similar problem? Do anyone have any idea what the error could be?