Hello Steve,
if you have telnet or ssh access to the box you can use CLI
telnet box-address
use the user/pwd needed
get enable access
router> enable
router# conf t
router(config)# line con 0
router(config-line)# login local
router(config-line)#end
test console access then if everything is fine:
router# write mem
a username/pwd pair must exist to use this.
Hope to help
Giuseppe