Failed to load dialog file Resource/UI/ClassMenu.res

If you look in your error logs and see this message:

 Error:Failed to load dialog file Resource/UI/ClassMenu.res
 Function trace:
 CGameUI::Start
 CGameUI::Initialize
 CBaseUI::Start
 CBaseUI::Initialize
 Host_Init
 CFileSystem_Steam::Mount() 

This is NOT an indication of a real error and it happens if you have a problem running your game or not.

Only TeamFortress has this file for real and no other game needs it, but for some reason when you run some (not all) of the Steam games, HL will go looking for this file and will create this message in the errorlogs if it can't find it.

You can very easily prevent the error message from being created by placing a dummy Classmenu.res file in one or more of the following folders (wherever you installed your games, <account> is your Steam account name):

C:\Program Files\Steam\SteamApps\<account>\counter-strike\cstrike\resource\UI\Classmenu.res

C:\Program Files\Steam\SteamApps\<account>\condition zero\czero\resource\UI\Classmenu.res

C:\Program Files\Steam\SteamApps\<acount>\condition zero deleted scenes\czeror\resource\UI\Classmenu.res

C:\Program Files\Steam\SteamApps\<account>\day of defeat\dod\resource\UI\Classmenu.res

Here is the dummy Classmenu.res file (right-click and save-as): Classmenu.res

NOTE: You might have your Steam Installed somewhere else, please adjust the above paths to fit your installation!

If you don't have those folders there then create them.

These four Games are the only ones that seem to generate this warning message, you shouldn't need to do this for any other games.

Also, If you are having trouble running HL, doing this probably won't help you fix your problem (but it won't hurt either).