I have an 877 router that will not connect to my ISP. I've tried the troubleshooting docs, when I run a PPP debug, I get Vi2 CHAP: O RESPONSE id 1 len 34 from <my isp username>"
Vi2 CHAP: I FAILURE id 1 len 42 msg is "CHAP authentication failure, unit 2965"
the username and password are for certain correct, and the line is ok, as when I use another (much cheaper) router, it works fine. I've wiped my router and re-done the config from scratch, with same result. I'm running the latest IOS. Any ideas what other troubleshooting can be done?