Sapgui error service sapdp00 timed out

Hi,

I am getting Sapgui error " connection to host ....,service sapdp00 timed out" when connecting to a remote sap system over internet. Earlier i could connect to the system without any problems. I am connecting to Internet thru a wireless network-cable connection & firewall is disabled. Recenly i configured home network(workgroup configuration) for file sharing with another system, after this configuration Sapgui is giving this error. I tried different ways but in vain. Can anybody help me regarding this.

Thanks

Pavan.