1. Delete the content of folder "C:\Documents and Settings\All users\Application Data\Symantec\LiveUpdate\Downloads\"
Note: Application Data is a hidden folder. Delete the content of the Downloads folder, but not the folder itself.

2. Stop the service "Symantec Endpoint Protection Manager".
To stop this service:

1. Go to Start > Run.
2. Type the following: Services.msc
3. Select and stop the above mentioned service

3. Delete the numbered or TMP folders inside the paths:

• %programfiles%\symantec\symantec endpoint protection manager\inetpub\content\{535CB6A4-...
• %programfiles%\symantec\symantec endpoint protection manager\inetpub\content\{07B590B3-...
• %commonprogramfiles%\Symantec Shared\SymcData\spcVirDef32
• %commonprogramfiles%\Symantec Shared\SymcData\spcVirDef64

Note 1: In Server 2008, the Downloads folder in step 1 is located at  %programdata%\Symantec\LIveUpdate\Downloads
Note 2: In 64 bit operating systems the "Symantec\Symantec Endpoint Protection Manager\inetpub\content" folder will be located in C:\Program Files (x86) and not C:\Program Files
Note 3: For Windows Server 2008 or similar systems the location of the %commonprogramfiles%\Symantec Shared\SymcData\ will be following: C:\ProgramData\Symantec\Definitions\SymcData\

4. Launch the process LUALL.EXE

5. Restart the Symantec Endpoint Protection Manager service when LiveUpdate is complete. 

1. Log on to Symantec Endpoint Protection Manager Console and launch a LiveUpdate from Admin > Server > Local Site > Download LiveUpdate content.
2. Verify the correct download/usage of new virus definitions from "Admin > Server > Local Site >Show LiveUpdate Downloads".