Overview:
As a WHM Reseller, you have top-level access to all cPanel services you have created from your admin area. Using the List Accounts tool you can log directly into cPanel accounts to troubleshoot, manage or review your clients' services in more detail.
Method:
Log into your WHM Reseller hosting area.
Navigate to the "List Accounts" tool, under the "Account Information" category.
Find the cPanel account you'd like to access. You can filter the cPanel accounts displayed by using the "Search for:" option.
Log into the cPanel account by clicking the orange "CP" button next to the domain name in the cPanel column.
You’re now logged into the cPanel service and can use it as the primary user