One (of several) Win7 PCs can't see XP machine

My LAN consists of a gateway/router and 4 PCs – A, B, C and D.
A thru C are Win7/64; D is XP32/SP3.

Until a few days ago, everyone saw and could access everyone. Then C stopped seeing D. C can ping D, but it can’t see it (in Network or in the network map).

C can still see itself and also A and B.

A, B and D can still see everyone.


I’ve tried all the usual fixes from this and other forums: verified that all have same Workgroup name (no Homegroup); checked the IPs and other adapter settings; checked sharing settings; disabled C’s firewall; rebooted everything and everybody. Also tried to use the LLTD hotfix, but Windows reported that my XP-SP3 install already has it.

I’d appreciate any suggestions. Thanks!

Most likely which ever A/V software you have installed is causing the problem. They can create rules out of thin air that will prevent machines from seeing each other.

The only A/V installed on the problem PC is VLC Media Player, and it's also installed on all the other machines without problems. But if you've heard of VLC causing problems, I'll try removing it.

VLC player isn't and A/V "anti virus" anyway, it's just for playing DVD's or .ISO's. But really no idea why your machines just stopped seeing each other.

I see I shouldn't have guessed at your abbreviation. (A/V is also audio-visual.) But I also disabled my anti-virus (Avast), and still no luck.

Anyone else out there have an idea?

You might try removing Avast with it's removal tool then check to see if those machines can see each other again. This is the usual cause for these types of problems and disabling the A/V won't fix it.

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