If the installation script of Avira Antivirus Premium, Avira Internet Security or Avira Professional Security reports that the installation of LSP (Layered Service Provider) failed, LSP has to be reset. It may happen, if Web Protection or Mail Protection is installed, along with another LSP-based program on the same computer.

Please note:
It may be possible, that some software is not working anymore after you have reset the LSP.
 

To reset the LSP on Windows XP:

1. Go to Start → Run
2. Type cmd and press Enter, to open the command prompt
3. Type the following command:
   

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   netsh winsock reset
   

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4. Press Enter
5. Restart the computer

To reset the LSP on Windows Vista/ Windows 7:

1. Go to Start → Programs → Accessories
2. Right-click Command Prompt and select Run as administrator
3. Type the following command:
   

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   netsh winsock reset
   

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4. Press Enter
5. Restart the computer

After the restart, you can continue installing Avira Antivirus Premium, Avira Internet Security or Avira Professional Security.

Therefore please perform a change installation:

1. Open the Windows control panel
   Windows XP / 2000: Start → Settings → Control Panel → Add or Remove Programs
   Windows Vista / 7: Start → Control Panel → Programs → Programs and Features
2. Select the Avira application (e.g. Avira Internet Security) and click on Change
   
   
    
3. Select Modify and click Next
   
   
    
4. Confirm all the following dialogs with Next as well
5. Restart your computer

The procedure is also explained in this video.

Please keep in mind that this problem may remain if LSP-based programs are still installed on the system, since they can repair themselves, i.e. renew their entry in the LSP-stack.