By default the Symantec Endpoint Protection Manager downloads and keeps a particular number of virus definition revisions in its repositories based on the type of install performed:

• Simple: A management server that manages fewer than 100 clients and uses an embedded database.
  • 3 revisions
                  
• Advanced: A management server that manages more than 100 clients or if you want to customize the configuration.
  • Between 100 and 500 = 3 revisions
  • Between 500 and 1,000 = 10 revisions
  • More than 1,000 = 30 revisions
                  
    This number can be lowered to help reduce the amount of disk space that is used by content revisions. The Symantec Endpoint Protection Manager must have previous content revisions stored in order to create a "delta", or differential, capable of updating a client from its version of that content type to the most recent type. For detailed information on how to determine how many content revisions to keep see the following: Best Practices for configuring the number of content revisions to keep in Symantec Endpoint Protection Manager
    
    How to change the number of revisions retained by the Symantec Endpoint Protection Manager:

1. Login to Symantec Endpoint Protection Manager
2. Click on the Admin tab
3. Click on Servers
4. Right-click on Local Site and choose Edit Properties
5. Click on the LiveUpdate tab
6. At the bottom under "Disk Space Management for Downloads" you can alter the number of content revisions to keep
7. Click OK
   
   

How to edit the database retention settings for the Symantec Endpoint Protection Manager to help save disk space:

1. Log in to the Symantec Endpoint Protection Manager
2. Click on the Admin tab
3. Click on Servers
4. Right-click on Local Site and choose Edit Properties
5. Click on the Database tab
6. Edit the retention settings here as desired
7. Click OK
   
   

References

• Troubleshooting Content Delivery to the Symantec Endpoint Protection client (2008092511045348)
   
• Symantec Endpoint Protection virus definition folder consumes a large amount of disk space (2007111509244948)
   
• Best Practices for configuring the number of content revisions to keep in Symantec Endpoint Protection Manager (2009020514050748)