TOPIC: having problem configuring switch...

i'm having trouble configuring my SMC 6248M switch. i did some simple config like create vlans, then assigned ports to the vlans....but i'm unable to untagged all the ports of the default vlan,which is vlan 1...everytime when i untagged it, copy the running-config to the startup-config,it will always reset back to none everytime i reboot it...pls help!!!