Hello,
One thing to keep in mind when setting up these switches is this. Whatever address you first statically set on the switch will become it's management address. As soon as you enter an IP for a VLAN interface it will remove the default address of 192.168.1.254. Try setting one address and then accessing the switch at the address you just set. I'm assuming your are telnet/SSHing in, you can also try the console cable so that when that IP address changes you will still have access to the CLI.
Hope that helps,
Christopher Ebert - Advanced Network Support Engineer
Cisco Small Business Support Center
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