The EXPRESS_SETUP-6-CONFIG_IS_RESET: [chars] error message means the configuration is reset. [chars] is a text message that clarifies the reset event.
If you press the Mode button for a total of 10 seconds or more in a switch configured for Express Setup, the switch configuration is deleted, and the switch reboots. The switch can then be configured like a new switch, either through the web-based Express Setup program or the CLI-based setup program.
For example, in these scenarios:
Scenario 1 When the mode button is pressed a little bit too much on the Catalyst switch and the system reboots without any configuration i.e., both running and start-up configuration.
Scenario 2 The config file and vlan.dat file of the switch are renamed to config.text.renamed and vlan.dat.renamed.
This problem is seen on Catalyst switches that run Cisco IOS Software Release 12.1(14)EA1 or later, which provides support for Express Setup.
This problem is documented in Cisco bug ID CSCee75743.
Disable the Express Setup feature so that the switch configuration cannot be deleted if the Mode button is pressed for 10 seconds. In order to disable the Express Setup feature, issue the no setup express.
Click Mode in order to verify that the Express Setup mode is disabled. The mode LEDs only turn solid green or begin to blink green if the Express Setup mode is enabled on the switch.
If the symptoms matches as described in Scenario 2, issue this command:
rename flash:config.text.renamed flash:config.text
rename flash:vlan.dat.renamed flash:vlan.dat
copy flash:config.text running-config