There seems to be a lot of confusion over the patch re released last month. If you try to join a server and get an error about your client dll differing from the server's, it means one of two things. Either you have not installed the patch correctly, or the server hasn't. If it's the server, there's nothing you can do except try a different one. If you seem to be getting this error on every server, it's more than likely that you haven't installed the patch properly.

You'll need to download it again, and get WinZip if you haven't already. Then you can right-click on the patch, choose 'Extract to...', then browse to you Firearms folder. This should be at C:\\Program Files\\Steam\\SteamApps\\your_username\\half-life\\firearms. You also need to make sure the 'Use folder names' and 'Overwrite existing files' boxes are ticked. Then you press the 'Extract' button and it's done.

The next patch is very near completion. We're just waiting for a couple of maps to be updated, and then we'll be able to get an installer done. Creating the installer will cause a slight delay, but with so many people having problems with a simple zipped patch, I think it's worth it. Hopefully we'll be able to get it released before next weekend.