Error "Specified username is invalid for device" during backup of cisco 3750

I confess I'm not familiar with Kiwi CAT Tools, but if I were to receive the same error message via a backup in NCM, I'd edit the device in NCM and run the test on the credentials there and see if it passed.  If not, you can easily enable device logging in NCM, duplicate the attempt, and then go to the logs and see what credentials were sent, and review what the responses from the switch were.

Don't forget the basics:

• The user name doing the backup is correct--including case
• The password is correct--also including case
• The backup server is not blocked from accessing the switch by ACL's on the switch or firewall rules
• TACACS (if you use it) has the correct permissions for the user to access the device
• TACACS/RADIUS has the correct key for the device
• The device is correctly entered into TACACS
• The user name is correct in TACACS for the device
• The user name has the appropriate permissions on the switch

I know you've covered some of these by doing the work manually.  TACACS or RADIUS and the switch (and NCM) will generate logs for the failed access; use them to troubleshoot what's happening.

Post your progress so we can learn with you!

Good luck!

HI,

Thanks for reply.

as mentioned there is no option in Kiwicat to check if credentials are passed & also logs won't show clearly what username and password.

Basics are thouroughly checked.

Have you tried enabling Capture Mode (File\Enable capture mode")?  This will show you verbose communication with your device.