How do certain Affiliate Marketing companies know I'm using proxies?

In the past I have used a vast array of sign up service VPNs, private proxies, etc. However on some new Affiliate Marketing companies there seems to be some sort of system in place that ALWAYS know when I'm using a proxy/VPN because instead of taking me to the landing page, it redirects me to some other page instead. And yes these are US proxies/VPNs. I feel the services I'm using are pretty obscure (including some private proxy services from this forum) How could they possibly have a database of every "non real IP" or are they detecting it some other way? Anyone have any advice? This is driving me nuts.

there is a reverse dns set up on the proxies or on the VPNs ips?

Hi,

They use services such as MaxMind which has several parameters to detect IPs to be from datacenters / proxies / and etc. Majority of the public proxies will be detected via that.

They scrape proxy lists like any other company but use it to filter the IPs and ban them. They also take lists from various sources of abuse .

Also ensure you disable Javascript / Flash we it would override your browser proxy config and reveal actual IP.