Can't Play Dota? An issue with your computer is blocking the VAC system. You cannot play on secure servers.

Restart your computer

An issue with your computer is blocking the VAC system. You cannot play on secure servers.

How do I fix this?

If this is a problem for you on all servers then you can try fixing this problem by exiting Steam and restarting your computer.

Conflicting Software

This issue can be caused by third party software interfering with your game or Steam. Please restart your computer, then launch Steam and the game without running any other third party software.

Common Conflicts:

• Cheat Engine
• IObit Start Menu 8
• CCleaner
• Process Hacker
• DLL Injectors

Repair the Steam Service

This may also indicate a Steam Service failure.  Please try repairing the Steam Service:

• Exit Steam.
• Click Start > Run (Windows Key + R)
• Type the following command:
  
  "C:\Program Files (x86)\Steam\bin\SteamService.exe" /repair 
  
  (If you have installed Steam to another path, please replace C:\Program Files (x86)\Steam with the correct path.)
  
  This command requires administrator privileges and may take a few minutes.
• Launch Steam and test the issue again. 

Restore Boot Settings to Default

Kernel Integrity checks, Kernel Debugging, and Data Execution Prevention (DEP) must be set to default to play on VAC secured servers. To change these settings to default please follow the steps below:

• Exit Steam.
• Click the Start button, then 'All Programs', and 'Accessories'
• Right-click on Command Prompt and click "Run as administrator..."

Note:

If you are running Windows 8 you will need to press Windows Key + X and select Command Prompt (Admin)
• In the command prompt, type the following commands and press Enter after each command:
  
  bcdedit /deletevalue nointegritychecks 
  bcdedit /deletevalue loadoptions 
  bcdedit /debug off 
  bcdedit /deletevalue nx  
   

Note:

If you recieve the following error when entering these commands they are already set to default.

The value is protected by Secure Boot policy and cannot be modified or deleted.
• Restart your computer.
• Launch Steam and test the issue again. 

Repair System Files

There may be corrupt system files that are causing this issue. The following instructions will run a critical system file check on your Windows installation, replacing any missing or damaged files:

• Exit Steam.
• Click the Start button, then 'All Programs', and 'Accessories'
• Right-click on Command Prompt and click "Run as administrator..."

Note:

If you are running Windows 8 you will need to press Windows Key + X and select Command Prompt (Admin)
• In the command prompt, type the following command and press Enter:
  
  sfc /scannow


• Once the operation has completed please restart your computer then launch Steam and test the issue again..