I run a small computer lab of 10 computers and occasionally, when using the network explorer (a.k.a Network Browser) some or all of the remote computers will fail to appear. If I try to access a remote computer by its name I get an unspecified error (code 0x80004005), but I am still able to access it with the computer's IP address. The strangest part is that the problem will inexplicably go away after waiting awhile.

Each computer is running Windows 7 x64 Enterprise and has identical hardware, software and configuration. They are all on the same subnet and in the same workgroup.

I've spent days researching the problem and have tried the following solutions:

1. Updated the BIOS, chipset and network adapter drivers
2. Changed Power Settings in Network Adapter Properties so that the computer will not turn it off
3. Disabled the Computer Browser service
4. Changed the DHCP node type to broadcast
5. Reviewed the Event Viewer logs

Steps 3 and 4 have seemed to help the problem a little bit, but not completely.

I'm beginning to suspect that the problem might lie with our router which is a ZyXEL ZyWALL 2WG, as the packets sent by Network Discovery may not be returning in time, but I wanted to get some perspective in the issue before I went any further.