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.
This is still an issue with us, default route is 0.0.0.0 with no gateway entry, manually rmoving it works but its not good enough, we are looking for a dynamic fix.
Is Apple Bonjour installed on all of the affected machines? If so, this may apply as Bonjour can set the persistent route – the fix is to run elevated command prompt (search command prompt, right-click, run as administrator) and enter
route delete 0.0.0.0
press enter
then type
exit
press enter
http://news.softpedia.com/news/Apple-Bonjour-Can-Kill-Vista-SP2-039-s-Internet-Access-109665.shtml
To check if you have the persistent route, use the command prompt and type:
route print
and look under “Persistent Routes” for “0.0.0.0”
OK, just found out: When you assign your computer a static IP address, Windows puts a persistent route with
Network address Netmask Gateway address Metric
0.0.0.0 0.0.0.0 Default
If you delete it, your internet won’t work. To get it back, simply go in to your network adapter settings and put your static IP info (IP, subnet mask, Default Gateway IP) back in.
That should read: Network address of 0.0.0.0; Netmask of 0.0.0.0; Gateway address of (your gateway IP); Metric of Default