1. Open a new HyperTerminal connection.

2. Give it some name and click ‘OK’.

3. Select the right line that you use to connect. (COM1; COM3; etc)

4. On the port settings window, click on “Restore Defaults”. This would change the settings to :
Bits per second: 9600
Data bits- 8
Parity- None
Stop bits- 1
Flow control- None

5. Now, you need to change only the first variable, “Bits per second”, to all the possible numbers to see if this resolves the issue. The other settings need not be changed. So, try all the baud rates one by one:
1200; 2400; 4800; 9600; 19200; 38400; 57600; 115200; etc.
Once you select any one of the baud rates and click on ‘OK’, see if the router echoes back exactly the same characters you type in. If it does, then this is the baud rate the router is currently configured with.

6. You may continue to console into it at this baud rate. However, you may want to change the baud rate back to the default value, 9600. The command to make this change on the router/switch is-
(config)# line console 0
(config-line)# speed 9600

7. Once it has been done, you would have to again change the baud rate on the computer also to 9600. So, close this Hyperterminal session; open a new session; choose the default settings; and console into the router.

8. This time you need to save the new baud rate on the router. Use the 'write memory' command to save the changes.