Hi.
First make sure that you have tried disconnecting power.
If switch is connected to routers, hubs, bridges or other switches, disconnect the devices to isolate the problem.
Disconnect power, disconnect all Ethernet cables from the back of the switch. Test the switch with only two connections. Test twice using two different pairs of Ethernet cables. If any of the 8 wires inside the Ethernet cable is shorted you may have recurrent network problems. To do things properly the cable should be checked using a
network cable tester,
If cables are OK keep using two connections and connect two computers or devices (e.g. test using one computer and one printer). To do the test using Windows go to command prompt and type ipconfig/all. If you see the other IP and the network stays, then the problem could have been caused by one of the connected devices. A defective network adapter, a server problem or a system problem may result in network dropping down every couple of minutes.
If that does not help consider that the switch itself may be defective. If the problem is the switch you can contact Cisco at
Support Cisco.Regards.
Ginko