Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have 4 computers all running Windows 7 networked in a workgroup through Billion 7404vgp-m wireless router. All drivers and firmware for wireless adapters and router are up to date.

Windows Firewall and Defender disabled. Disconnected ipv6. Running Nod 32 anti virus software. All have own static IP address 192.XXX.X.XXX.

When I reset the router, all computers have Internet and LAN access for about 1 hour. And then they will lose the LAN connection but maintain Internet connection. Resetting wireless adapters or restarting computers does nothing to fix this but resetting router will.

What is causing this? How do I fix it?

share|improve this question

migrated from Mar 27 '10 at 14:53

This question came from our site for system and network administrators.

What netmask does the router use for the WLAN? – Fred Mar 31 '10 at 17:08
Do you mean Subnet mask? It is – Di. Apr 3 '10 at 4:35
What do you mean by "lose the LAN connection"? What exactly happens that makes you think lost their LAN connection? (And if they lost their LAN connection, how could they still have Internet access?) – David Schwartz Jan 19 '14 at 23:44

Finally solved my problem -sort of!! It turns out that on the Billion 7404vgp-m router in Wireless Security settings is a setting called 'Group Key Renewal' and has a value set in seconds. It was set to 3600 seconds (1 hour) and that was how long the LAN would stay connected. I changed this value to numerous values and the LAN would always stop working at the time I set in 'Group Key Renewal'. I have now set the value at 86400 (24 hours) and it works well as I usually turn off the router at night. I have put Nod32 on with now problems. I continue to have Windows Firewall, Defender and Security Center disabled.I have setup a WorkGroup called 'Home' as it was simpler for my usage. Given that all computers have different NICs and system components but all have Windows 7 Home installed and setup with the same configuration I feel it is something Windows7 is checking with the router that causes this problem.I had these same computers with the same configurations running a LAN on Windows XP Home/Professional and the LAN worked fine. If there is a way to fix this I would still like to know. Hope this helps someone else.

share|improve this answer

The alternative which works is to set the Group Key renewal period to 0. The group key then is never renewed. This means that your wifi system is not quite as secure as it could be. It could be possible for someone with enough knowledge in close proximity to your router to eventually hack in. The big advantage is that your wireless connected computers are never disconnected from each other and from the server. I will risk that.

share|improve this answer
it may be less secure. But never renewing the key really mean your wireless modem never "locks" and requires a hard restart. I know what my 7404 setting is set to...!!! – user106988 Nov 27 '11 at 6:05

You must log in to answer this question.