Windows 7 intermittently drops wired Internet/LAN connection

"SOLUTION FOUND:

I feel incredibly embarrassed to admit this, but I finally found the solution to my problem and, for me and my problem at least, it was a very easy fix.

In a nutshell, it was a dodgy network cable between my PC and my router. Although brand new, the cable was obviously intermittently defective, and replacing the cable (ironically, with my older, more battered and twisted but perfectly functioning network cable), my LAN has worked perfectly ever since without a single ""drop"". (And this is over the course of 4-5 weeks of ""testing"" to ensure that the intermittent problem had really disappeared).

What is interesting, and what completely threw me off the ""scent"" of looking at the physical hardware was how the problem manifests itself in Windows 7.

Basically, there must have been a slightly loose connection or wire in the LAN cable. When this would ""break"", Windows would show a broken LAN icon in the task tray area. This would remain broken until I manually went into the LAN Adapter properties, disabled the LAN, then re-enabled it. It was this software-driven temporary ""fix"" that lead me to believe that the fault itself was entirely software (ie. Operating System) based, rather than physical. Every time the LAN icon would show as ""broken"", I could ""fix"" the issue with this disable/re-enable series of steps. Every time!

After exhausting all the software avenues, I started on the hardware. I changed my router for a different one at first and that didn't ""solve"" the problem. Then I tried the LAN cable. Bingo!

Of course, due to the intermittent nature of the problem, every time I'd try something new, I'd have to ""run with it"" for a number of weeks to ensure that the problem had gone away (or not, in most cases) since even when the problem was there, I'd been able to go for 5-7 days without a single LAN ""break"" prior to the issue rearing it's ugly head again. This explains why I'm answering my own question 4 months later! :)

I've now been running with my new (old) LAN cable for 4-5 weeks, and in that time the network connection has not dropped once. I therefore believe I've fixed my problem.

I'm sharing my solution here in the hope that anyone else suffering from the same symptoms can try changing the LAN cable first (despite the symptoms looking very much like a software problem!) :)

I'd also like to thank everyone that responded with various suggestions! Thanks!"

"Unbelievably, my drops from my Lenovo ThinkPad Y460 were almost entirely from the laptop going to my wireless box and that was the only computer running Windows 7.

My router is connected to a wireless bridge, which works flawlessly.

I shut down the Windows firewall, installed ZoneAlarm and the problems are gone.

Get rid of the Windows Firewall and use something like the free ZoneAlarm."

"I worked on this type of problem myself and found it was a conflict with IPv6 and the router.

Essentially, disabling IPV6 on all Windows 7 and Vista machines resolved the problem for the entire network. I wrote more details on this in a blog."

"The same is for me (Windows 7 Ultimate 32Bit + VMWare + Intel 1000/PM adapter).

I believe the problem is in power management – I've disallowed to ""Turn off device to save power"", and updated the driver from Microsoft to Intel.

It solved the problem."

"I had this issue on new Dell laptops with Windows 7, the post by Brian Rasmussen clued me in, I removed the Dell Control Point and security software suites. This seems to have resolved the issue of the wired NIC card dropping off.

It would happen about every 10 minutes, the |Internet access would stop then the network access. Running the network troubleshooter would resolve it by reseting the NIC card. This seemed odd to me until I looked at the power options in the control panel and there was a Dell Control Point selection there for the NIC card. I also set the power option to never turn off or sleep while plugged into power.

I hope this helps someone."