You need to put the original 2.60b et.exe into the Steam version: https://download.hirntot.org/et2.60b.zip (Virus Total link: https://www.virustotal.com/gui/url/9f17387e1e7e6af731368dab266331cc9e46da85ba175298c3712173a0390653?nocache=1 )

And then install PunkBuster: https://download.hirntot.org/ET_PBSetup.exe (Virus Total link: https://www.virustotal.com/gui/url/eb57177dd8796b85798bb9b3f1b878914465dad7f5c41b492c32501b11573bd0?nocache=1 )

Then you can play on the oldest ETPro community server still alive, online since 2004, with an active playerbase and daily games on a full server half the day without any bots (ETPro doesn't support bots), /connect et.hirntot.org in console.
Edit: we have changed to ETLegacy, you can follow this guide instead: https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=2800452649

You can also join our Discord: www.hirntot.org/discord

If you're having any FPS issues, /r_primitives 2 or r_ext_multisample 0 in console might help. If using NVIDIA, disabling threaded optimization in the driver settings helps too.

Slow downloads? /cl_wwwDownload 1

For custom resolutions:
/r_mode -1
/r_customwidth 1920
/r_customheight 1080
/r_customaspect 1
/vid_restart

If video is stretched in-game:
Right click et.exe and check "Disable display scaling on high DPI settings" or alternatively "Override high DPI scaling behaviour. Scaling performed by: Application"