Unable to write to flow.xml

I am running IS 6.1 w/SP1 on Windows 2000 Server, I get this following when creating new flow service but no problem on creating new Java, C service. I have tried to restart the server but still fail. Can someone help this for me?

com.wm.app.b2b.server.ServiceException: [ISS.0026.9103] Unable to write to flow.xml
at wm.server.nsimpl._putNode(nsimpl.java:5920)
at wm.server.nsimpl.makeNode(nsimpl.java:4906)
at java.lang.reflect.Method.invoke(Native Method)
at com.wm.app.b2b.server.JavaService.baseInvoke(JavaService.java:287)
at com.wm.app.b2b.server.invoke.InvokeManager.process(InvokeManager.java:587)
at com.wm.app.b2b.server.invoke.StatisticsProcessor.process(StatisticsProcessor.java:44)
at com.wm.app.b2b.server.invoke.ServiceCompletionImpl.process(ServiceCompletionImpl.java:229)
at com.wm.app.b2b.server.invoke.ValidateProcessor.process(ValidateProcessor.java:49)
at com.wm.app.b2b.server.ACLManager.process(ACLManager.java:194)
at com.wm.app.b2b.server.invoke.DispatchProcessor.process(DispatchProcessor.java:39)
at com.wm.app.b2b.server.AuditLogManager.process(AuditLogManager.java:403)
at com.wm.app.b2b.server.invoke.InvokeManager.invoke(InvokeManager.java:503)
at com.wm.app.b2b.server.invoke.InvokeManager.invoke(InvokeManager.java:367)
at com.wm.app.b2b.server.ServiceManager.invoke(ServiceManager.java:246)
at com.wm.app.b2b.server.comm.DefaultServerRequestHandler.handleMessage(DefaultServerRequestHandler.java:119)
at com.wm.app.b2b.server.HTTPMessageHandler.process(HTTPMessageHandler.java:167)
at com.wm.app.b2b.server.Dispatch.run(Dispatch.java:298)
at com.wm.util.pool.PooledThread.run(PooledThread.java:105)
at java.lang.Thread.run(Unknown Source)

Hi Kevin,
Is your IS directory structures mapped to a VSS or other source control mechanism? In that case until, you check out these files from the source control, you will not be able to edit flow. If the corresponding Java dir is not mapped to the version control, it will allow you to do it.

HTH,
Bhawesh.