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Introduction
This document explains how to recover Cisco Catalyst fixed configuration switches from a corrupt or missing system image or an incorrectly set boot variable. The Catalyst fixed configuration switches that this document describes include the 2940, 2950/2955, 2970, 3550, 3560, 3750 and the 3750 Metro series switches.
Prerequisites
Requirements
If you have not already done so,connect a PC to the console port of the switch. For information on how to connect a terminal to a Catalyst fixed configuration switch, refer to Connecting a Terminal to the Console Port on Catalyst Switches. Use a terminal emulation program such as Microsoft Windows HyperTerminal in order to establish the console session. These are the settings:
* Bits per second: 9600
* Data bits: 8
*Parity: None
* Stop bits: 1
* Flow control: None

Components Used
This document is not restricted to specific software and hardware versions.
The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand thepotential impact of any command.
Conventions
Refer to Cisco Technical Tips Conventions for more information on document conventions.
Problem
When Catalyst fixed configuration switches experience boot errors, these conditions can apply:
* The switch is in a continuous reboot.
* The switch displays the switch: prompt.
* The error loading flash: message appears.
Switch Displaysthe Switch: Prompt or "Error Loading Flash:"
* The switch: prompt indicates that the switch has not booted completely and requires the user to complete the boot process.
* The error loading flash:<image> message indicates that the switch failed to load an image because of a corrupt or missing image.
The corrupt or missing image can be the result of a failed download. In thiscase, the image has a bad checksum or a failed software upgrade, and the upgrade procedure was not followed properly. There is the possibility that the user deleted the image but did not replace the image. A boot variable can have been set incorrectly.
With a console session open, you see an error message that is similar to this:
Error loading "flash:c2950-i6q4l2-mz.121-12c.EA1.bin"Normally, the switch attempts to automatically boot the next valid image in the Flash file system. Here is an example:
Error loading "flash:c2950-i6q4l2-mz.121-12c.EA1.bin"
Interrupt within 5 seconds to abort boot process.
Loading "flash:/c2950-i6q4l2-mz.121-13.EA1.bin"...##############################################################

!--- Output suppressed.

If there is no valid backup image from which to boot, the boot process fails completely. Here is an example:
Error loading "flash:c2950-i6q4l2-mz.121-12c.EA1.bin"
Interrupt within 5 seconds to abort boot process.
Boot process failed...
Step-by-Step RecoveryProcedure
Use this solution to solve the problem.
Note: A PC must be attached to the console port of the switch, as the Prerequisites section of this document states.
1. If the switch is in a continuous reboot, complete one of the procedures in this step, which depends on your switch model.
Note: If the switch is not in a continuous reboot, but is already at the switch: prompt, proceed directlyto Step 2.
* Catalyst 2940 and 2950 series switches

a. Unplug the power cord.
b. Hold down the MODE button while you reconnect the power cable to the switch.
The MODE button is on the left side of the front panel.
c. Release the MODE button after the STAT LED goes out.
Note: The LED position can vary slightly, which depends on the model.
You are now at the...