An update to Team Fortress 2 has been released. The update will be applied automatically when you restart Team Fortress 2. The major changes include:

• Fixed a crash caused by using -dxlevel commands
  
• Fixed some ABI compatibility regressions for server plugins/mods
  
• Fixed a crash under 64-bit caused by some custom HUDs using Half-Life 2 HUD elements which assume the player is Gordon Freeman
  
• Fixed a crash when opening options/going into game (mostly affecting Windows 7 users)
  
• Fixed the snd_cull_duplicates command not working
  
• Fixed a hang when importing cosmetics into the Workshop tools to upload
  
• Fixed an issue selecting surround sound audio settings (Headphones, 4, 5.1, 7.1, etc.)