February 20, 2010
Umm, a pretty decent topic I believe. Recently I was trying to figure out certain networking issues at a friend’s place and while running the command found a persistent route ‘0.0.0.0 0.0.0.0 gateway’ under the IPv4 settings and was sure that I didn’t add this entry at any point of time with my fresh Windows 7 professional installation. I wanted to see what will happen if I remove the same entry.
I removed the entry and everything seemed working perfect. I was still able to connect to internet, access other computers over the LAN etc. The problems started after the weekend when I took the laptop back to work and tried to connect to Microsoft exchange server using Microsoft Outlook (2007 standard edition)!
Outlook was so stubborn and shown me it was disconnected and I started removing the Java VirtualBox, ISA client etc and after going through few restarts still Outlook looked adamant and refused to connect to the exchange server. I checked with my colleague Sherin to confirm whether his 32bit Windows 7 professional has a persistent entry for the route and he reported yes.
I put the 0.0.0.0 persistent route entry back and bingo, Outlook got connected. The route entry 0.0.0.0 was a default entry against the default gateway for the session with Windows XP (if I am recollecting it correctly) and seems Windows 7 has made it as a persistent route with the latest enhancements!
If any Microsoft techies are reading this post (ever), would like to hear an explanation from them about this.