If you have SSH access, they're generally in /var/log and can be viewed as (in the below command I have my access logs set to be combined in one file, yours may utilize the error_log file):
Code
cat /var/log/httpd/access_log|grep 406

I'm not sure where it'd be on CPanel (in this case, it's likely building an error_log in the directory of the script, versus a centralized location), I'm not a fan, especially since VirtualMin is free and does the same thing tongue.

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