Missing Network Devices/Computers

TheSchaft said:

HRM, et. al. -

Looks like I found the problem. I had COMODO set too tight, and it was not allowing "system" to do multicast. I loosened up the restrictions in the COMODO firewall and it looks like that has solved the problem.

Thanks for all the help and suggestions. I need to study up more on the firewall stuff, it would appear - embarassing as I do computer security for a living - <sigh>

To be honest, there is no reason to be running a firewall on a computer in your own private network. The firewall in the router alone is enough. And if you really wanted to be running a firewall just use the one built into Windows 7. Its more then capable. The built in one also has the advantage of only turning on when you join a public network, that is when you really need it.

TheSchaft said:

logicearth -

I partially agree with what you say.

The router keeps the LAN hidden and catches most of the bad activity. However, I've found that MS Media Player has a bad habit of sending information someplace, for some reason, so I like to stop it.

There are some other programs that like to "phone home" also, and I like to be able to control what goes out of my system. Just paranoid I guess. <shrug>

You can do all that with the built in firewall, just set it to block from the properties in "Windows Firewall with Advanced Security". Or go into the Outbound Rules section and set Windows Media Player, down in the list to block.

It's a common misconception to think a hardware firewall is enough.

It only protects you from unsolicited incoming packets.

It does not protect against solicited incoming packets.

This means a program like a trojan, keylogger or a program that just want's to send info to the internet can easily bypass the routers firewall.


A tip for TheShaft.

When troubleshooting network problems, ALWAYS turn off all software firewalls.

From your first post I deducted you had good knowledge of networking, so I wrongly assumed you would have thought of turning firewalls off.

Nice to learn that your problem is solved.

Greetz

squonksc said:

It's a common misconception to think a hardware firewall is enough.

It only protects you from unsolicited incoming packets.

It does not protect against solicited incoming packets.

This means a program like a trojan, keylogger or a program that just want's to send info to the internet can easily bypass the routers firewall.

Yet the malware is already on the computer with full control over that computer, which in turn can make any changes it wants which could allow it to bypass any security software running making the whole point moot.

The best defense is not to get any of that on your computer in the first place.

logicearth said:

Yet the malware is already on the computer with full control over that computer, which in turn can make any changes it wants which could allow it to bypass any security software running making the whole point moot.

Nonsense.

You are only right in case one never checks the firewall rules to look for anything fishy.

That's why you are right in 99% of the cases.


@Theshaft,

I can see your point, but you make a wrong jump in your thoughts. IMHO

If you had disabled the firewall, you would instantly know the problem lies somewhere in there, thus saving you time looking in other places.

From there you could examine the firewall further.

If turning it off made no difference, you could instantly rule it out.

Greetz