I am also having this issue with three Vista Business laptops that refuse to time sync to the network PDC. There are four others that are working fine and I can find no difference between them. I have checked the group policies (all four set to not configured) and checked the registry. I have run net time /unregister the /register. I even forcus the registery to point to the time server. Nothing works. w32tm /resync (/rediscovery) replys no time data available.Loaded and ran netmon. w32tm resync did not produce any traffic that I could see.I can stripchart the PDCe from the client and the reverse, but the PDCe will not sync the client either. It does sync the working ones.Net time /set does work. But from the PDC w32tm /resync /computer:<client> does not. It also produces the no time data available.I can run a w32tm /stripchart to the time server.I are the resync with debug and the first line that differs on the computer with the issue is:ClockDispln TimeSlip:TimeSlip LastUTC:160538 SetUnsync: LI:3 S:0 RDl:0 RDs:0 TSF:0x0I opened ports UDP 37 and UDP 123 on the windows firewall of the client. w32tm was already there.Any assistance would be appreciated.