Laptop cannot see other PC's but Network Map Shows them

I have a home network called 'workgroup' on my win 7 laptop i see my xp desktop and my win home server machine. I used to be able to see these machine under the 'network folder' in the explorer but now the laptop cannot find or detect them. I have checked that home group is not being used, that the windows firewall is off, that the advanced setup for the home network has discovery turned on. The other machines on the network see each other so it is a problem with some setting in the win 7 machine that has changed because it used to work fine.

Tried it with the set up new connection but since i am already on the network and working fine it does not come up with unconfigured devices. The win 7 machine works fine with the only exception not being able to see the other machines.

Just about any anti virus software or third party firewalls can create rules to block other machines on the network.

I would check out your A/V software first.

Turned off the microsoft security essential which is my A/V and no difference. Also when it worked previously the A/V was on.

dmw said:

Turned off the microsoft security essential which is my A/V and no difference. Also when it worked previously the A/V was on.

MSE won't cause these types of problems. You should leave the Windows firewall turned on.

You might try looking in the Advanced Network settings and make sure network discovery is turned on and other networking services are turned on.

You might also try looking at the services.msc to make sure the ones related to networking are turned on and set to either automatic or manual.

Good suggestion on services, all were already correct so not a solution however good to know.

It might be worth using the network and trouble shooting wizards.
How to Troubleshoot Network & Internet Problems | 7 Tutorials

This is an ongoing problem with no clear solution. I've read about it plenty of times.

Check netbios over TCPIP is enabled on all machines and UPNP is enabled on the router.

When a Win 7 machine cannot see other XP or WHS based machines all the usual Netbios TCP/IP, Homegroup turned off, and turning network discovery on is the first thing to do. If it still does not work then the real fix is likely what I found to be a registry entry that somehow gets a state change that causes the issue.
Registry Location:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Netbt\Parameters
Key: DhcpNodeType
Value Type: REG_DWORD - Number
Valid Range: 1,2,4,8 (B -node, P-node, M-node, H-node) Mine was at 2 which is wrong it needs to be 8
Default: 1 or 8 based on the WINS server configuration
Description: This optional parameter specifies the NBT node type. It is written by the DHCP client service, if enabled. This parameter determines what methods NetBT uses to register and resolve names. A B-node system uses broadcasts. A P -node system uses only point- to-point name queries to a name server (WINS). An M -node system broadcasts first, and then queries the name server. An H -node system queries the name server first, and then broadcasts. Resolution through LMHOSTS and/or DNS, if enabled, follows these methods. If this key is not present, the system defaults to B -node if there are no WINS servers configured for the network. The system defaults to H -node if there is at least one WINS server configured.