Steps (11 total)
Connect the console cable to your PC
The first step is to connect a console cable to the COM port of your workstation to gain access to the switch. If your workstation doesn't have a COM port, you'll need a Serial to USB adapter as seen below.
Serial To USB Adapter
Verify that it is a console cable
Below is a link to a standard Cisco console cable & attached is a picture to reference if you want to make sure you've got the right cable.
Download Putty and Start a Serial Connection
There are several software products that will allow you to do this, but I recommend using Putty. It is the most accepted and easiest to use in my opinion.
To gain access to the console launch Putty and select the Serial radius button.
Download Putty Here
Double Check Serial Settings
To connect to a Cisco device via a Serial session a few settings need to be confirmed.
COM Port - (be sure the COM number is correct, if you are using a usb adapter it may not default to using COM1. It could be COM3 or 4, You'll need to confirm by looking in device manager)
Data Bits - set to 8
Stop Bits - set to 1
Parity - set to None
Flow Control - set to None
Once the settings are confirmed click Open, which starts the session.
Plug in the Console cable
Now with the terminal windows open, plug the console cable into the console port of the switch typically located on the back and labeled console.
Hold the mode button on the from of the switch
Before powering on the switch hold the mode button located at the front of the switch on the left side.
Power on the switch
Cisco Switches do not have an on\off switch, they are simply powered on by supplying power to them. At this now while still holding the mode button down, plug in the power cable.
Release mode button once it boots
Once characters are displayed on the screen release the mode button.
Press ctrl + pausebreak on the keyboard
While the boot process is in order hit ctrl+pausebreak on your keyboard. If you are using a laptop may need to use a usb keyboard to hit these keys.
Enter the following commands
Rename Configuration files & Remove passwords
Would you like to enter the inital configuration dialog? no
Switch > enable
SW1#copy flash:config.text system:running-config
SW1(config)#no enable secret.
You now have gained access to the switch and successfully returned it to factory default. You may also want to delete the vlan .dat file as it is not removed in the process of deleting the start up or running config.