[AdelCraft]

Hi,

I'm struggling to login into a website that has server-side login attempt counter lock. I've tried logging from different IPs and changing the user-agent, without any results.

What can I try next?
Thanks.

[f1re_w1re]

Nothing, that's what brute force protection is meant for. Only if you can use your attack in tandem with a chain of proxies where they know where to continue on the last attempt will you be able to look at the possibility of success. I can easily make an engine that can detect this and also determine the behaviour of your attack. That's why people refer to brute force as primitive.