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ISP/DC User:Pass Guide

Go to your dashboard and click Proxies → Manage → DCs Subscriptions.
Scroll down and click on the proxy type (Captcha, ISP or DC) you want to manage.
Go to your order and click Manage Order.
Select Credential Authentication on your proxy page and then click Enable Now.
You should now be able to copy the proxy list and use them.
You don't have to use IP authentication if you're using credential authentication for your proxies. Same for IP authentication, you do not have to use credential authentication if you're using IP authentication.