I have four separate computer labs - each using DHCP, and I have another connection used for video conferencing. Last night, one of the labs as well as the video conferencing connections were not working. All of the other labs as well as my machine were able to connect to the network. Each machine is able to ping loop back, but no where else. We are connected from this building to another via wireless. Someone suggested that the antennas on the roof would be messing the connections up, but wouldn't this have an effect on ALL of the connections? I've been in this position for only a couple of months without prior networking experience, so I'm learning as I go. I could use some help in stepping out the possibilities. Thanks