Vista Ultimate + Wired Connection - LOCAL ONLY on network change

My system running windows Vista Ultimate 64-bit has a Wired Connection and i transfer huge files from my system to my office on network. Since the files are large i put my system to sleep while carrying out the transfer. My problem is that when i wake up the system then i face "Vista Local Only and No Connectivity" problem . I have to go in to Manage Network Connections and re-enable the connection every time. I don't know what exactly is messing up the connection and i want to know if there is any solution that i can try to fix it.

Did you try updating your router's firmware and your NIC driver to the latest??? If not then try do it now and let me know if you issue gets solved, best of luck.

Yes you should firs try your routers firmware and your NIC driver. In case problem continues then you can go through below article and try out the resolution mentioned there.
The default gateway setting is lost when you wake a Windows Vista-based computer from sleep
It addresses similar kind of issue, the cause of this issue is said to be DHCP Client service (Dhcpcsvc.dll). You can know about everything in detail after going through the article.