× Few antiviral products inadequately detect 3proxy as Trojan.Daemonize, Backdoor.Daemonize, etc and many detect 3proxy as a PUA (potentially unwanted program). It may cause browser warning on download page. 3proxy is not trojan or backdoor and contains no functionality except described in documentation. Clear explanation of this fact is given, for example, in Microsoft's article.

3proxy Windows Authentication plugin

Support for cleartext authentication against Windows domain or local Windows account.


  1. Extract WindowsAuthentication.dll to the same folder with 3proxy executable.
  2. Create 3ProxyAllowedGroup - Windows system group allowed to use proxy. You can choose different group name. Group can be either local or Active Directory. Every account allowed to use 3proxy must be included in this group either directly or through group nesting.
  3. Configure plugin with 'plugin' command in 3proxy.cfg, e.g.:
    plugin "WindowsAuthentication.dll" WindowsAuthentication "3ProxyAllowedGroup"

    WindowsAuthentication.dll - location of DLL, if DLL is located in different folder from 3proxy.exe you must specify complete path to DLL here. 3ProxyAllowedGroup - Windows system group allowed to use 3proxy. After plugin is loaded, 'windows' authentication type is supported.
  4. Configure 'auth windows' for services that require Windows authentication.
  5. It's recommended you also configure authentication caching (see 'authcache'), to prevent excessive workload for domain controller. Example:
     authcache user,pass 900
     auth cache windows
  6. NTLM authentication is not currently supported for plugins, you should use proxy -n key to disable it.