Some weeks back, I installed four new W7 OS PCs and MS Office 2010, together with a new W7 compatible MFD at a Client's site. All four PCs are Cat 5 routed through a TP Link Router. The supplier of the PCs named each PC - WORKSTATION 01, 02, 03 AND 04. I then created and added these to a WORKGROUP and shared various folders across the network, configured firewall settings, folder sharing at each PC and advanced sharing, turning on Network Discovery. I left the IP address allocation as dynamic - through DHCP. I had these machines netowked through the Worhgroup at home before I physically installed them at the client's site, so I could pre-install updates to both the OS and MS Office etc etc and also test the driver updates on two other periferal devices. All went fine, including the site install. However, a few weeks back, the Client started reporting that the navigation to each of the workstations via MS Explorer (under the Network tree) started dropping out - but only for Workstations 02,03 and 04 - Workstation 01 never looses the ability to navigate to the other 3 machine's shared folders. Having read a lot of posts on Workgroups, the jury seems to be out on the benefit of TCP/IPv4 static IPs rather than DHCP allocations, but, in attempting to solve the issue, I've done this anyway. But this doesn't seem to have resolved the issue as the Client advised that MS Explorer visibility of Workgroup shared folders on Workstation02,03 and 04 dropped out again. I have a Homegoup set up at home and this has functioned flawlessly - sharing one router hard wired W7 Desktop and 2 wirelessly connected Lap tops. Can anyone give any insight as to what could be causing this "drop out" and only on Workstations 02,03 and 04 and in the afternoons? The Client boots up all 4 PCs in the morning and leaves them on. I've compared Ipconfigs and can't see any difference between Workstation01 (that always is able to MS Explorer navigate) and the other 3 that "drop out". Would I be better mapping each PC as a netowk drive and sharing folders via the static IP route of each PC? Cheers for any assistance! Colin

Legacy XP connectivity was based on open port 445. For visibillity ports in the range 137-139 play the role. For troubleshooting issues try co compare open ports and correct wrong ones. If this does not help, disable firewall temporarily (All Wks) and check netbios resolution nbtstat (see for parameters with /? ) Rgds Milos

Legacy XP connectivity was based on open port 445. For visibillity ports in the range 137-139 play the role. For troubleshooting issues try co compare open ports and correct wrong ones. If this does not help, disable firewall temporarily (All Wks) and check netbios resolution nbtstat (see for parameters with /? ) Rgds Milos

Ok Milos, will look into that - cheers for the response! :) Regards Colin