To prevent Firefox extensions from being disabled, you need to create a VirusScan Access Protection rule.

Create a User-Defined Access Protection Rule for Files/Folders in ePolicy Orchestrator (ePO):

1. Log on to the ePO console and click Policy Catalog.
2. From the Product drop-down menu, select the version of VirusScan Enterprise you use on your end nodes.
3. From the Category drop-down menu, select Access Protection Policies.
4. Click Edit Settings on your assigned Policy.
5. Click User-defined Rules, and then click New.
6. Select File/Folder Blocking Rule, and type a name for this rule.
7. Under Process to include select the asterisk (*).
8. Under File or folder name to be blocked add:
   
   **\firefox\**\extensions*.*
    
9. Under File actions to prevent, select:
   
   
   • Write access to file
   • Files being executed
   • New files being created
   • Files being deleted
      
10. Save your changes.