RPC server not available. In a standalone????

Hi all,
I have this application that i've made in VB .NET. It basically automates office application in the sense that it uses MS Excel as the backend. The data is written in the excel sheets and is displayed from the same in the frontend.
My system is Win 2k and the client's system is Win98, both on diff. LANs.
Now the problem is that this application works purrrfectly on my system and and our other win98 systems. But the same doesn't work on the client's System. Whenever we perform some event(as in click to retrieve excel data), Their PCs show this error:
"The operation could not be completed. The RPC server is not available." And then the application hangs.
I have no idea why this is coming... I am not using any resource on LAN.
There is a problem listed in the MIcrosoft site regarding the Office objects not being closed.
"Office Application does not quit after Automation from VS .NET client"
So, i have put a timer based code that, after every 15 seconds, checks for any existing "Excel object" in the task manager and if it finds one, terminates it.
like : - "Process.kill()"
Need help on this urgently.
Thanks in advance for any advice.
rajtofar