PC Not Accessible, You Might Not Have Permission To Use This Network Resource

[pc name] not accessible. You might not have permission to use this network resource. Contact the administrator of this server to find out if you have access permissions.The specified server cannot perform the requested operation.Lately we have had problems with all Windows XP pcs not being able to access all the shared folders on one Windows 7 pc on the lan.It is intermittent. I cannot think of what has changed recently.It is temporarily fixed by a reboot of the Win7 pc, but since it is a server in an office environment, this can be difficult to do middle of the day.Turning firewall software off on host and client has no effect.Network sharing profiles are never changed as issue comes and goes.Unsharing a folder, and resharing it has no effect.The Win7 pc does show up as a networked computer and all are in the same workgroup.All Windows 7 pcs on the lan can access the shared folders when all the XP pcs cannot.Another Win7 pc on the lan is nearly an identical hardware build with same firewall and never has a problem.

Network sharing options for current profile:

network discovery: on
file printer sharing: on
public folder sharing: on
media streaming: on
file sharing connections: 40-56 bit encryption
password protected sharing: off\

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