Dev License: This installation of WHMCS is running under a Development License and is not authorized to be used for production use. Please report any cases of abuse to abuse@whmcs.com
How to blacklist an IP Address to deny it access to your website?
You can lock directory with a password by using cpanel "Password Protected Directories" option.1. Log into your cpanel account.2. In the "Security" section, click on "IP Blocker" Icon.

3. Under "Add an IP or Range" you should enter the IP Address .block... "Add" babies.
Here is Example:Single IP Address: 192.168.0.1Range: 192.168.0.1-192.168.0.40Implied Range: 192.168.0.1-40CIDR Format: 192.168.0.1/32Implies 10.*.*.* -- 192.
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