Ok easiest way for me is to query the registry:
SYSTEM\\CurrentControlSet\\Control\\Class\\{4D36E972-E325-11CE-BFC1-08002BE10318}
Where {4D36E972-E325-11CE-BFC1-08002BE10318} is the class guid for network adapters. Then i can parse for my GUID in NetCfgInstanceId.
Regards