Hi,
It is possible that the console speed has been altered from 9600 on the switches. If you have telnet access to these switches, check the speed under 'line console 0' and use the same baud rate in the terminal emulation program on the PC (hyperterminal etc.)
If you do not have telnet access, try connecting with a baud rate of 115200.
Hope this helps,
Shashank
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