Hi Experts, this one has got me stumped... We have 4 servers on our SBS 2003 domain. We have about 40 users on our network. For the last week at about the same time in the afternoon for about 1-2 hours, I have about 6 users on the domain that loose connectivity to the primary domain controller. Users are spread out in different locations that are connected to managed switches ,so not just one switch/location that people are experiencing the issue. I am unable to ping the PDC from those users, however network shares to other servers are fine and I can ping member servers with no problem. Email and internet for those users are down ( services provided by the PDC). Also these users share the same POE connection to their IP phones and the phones work just fine as well. I have serveral Procurve switches that I have been monitoring and I do not see any excessive traffic and all ports on the switches seem to be operating just fine. I check the event viewer on the PDC and absolutely nothing in the logs that would hint to a problem. I also checked DHCP all leases are fine, no confilicts.
Any ideas on what I should look at to try and narrow this down?