Overview

This article addresses an issue where you are unable to add a Custom File Type when creating a new policy in GFI WebMonitor. 

Root Cause

Adding a Custom File Type requires adding the full Content-Type header of the file being accessed from the webpage in the Manage File Types popup window, under the Custom File Types Module. The issue described herein is a consequence of not adding the full Content-Type header of the file in question. 

Resolution

The solution requires two steps:

Step 1: Find the Content-Type header of the website

1. Download and install either Telerik Fiddler or Wireshark on the client machine that is using the WebMonitor proxy.
2. Launch Fiddler/Wireshark and access the webpage to view the Content-Type header of the audio/video file you want to block when accessing. For example:
   
   

   POST /foo HTTP/1.1
   Content-Length: 68137
   Content-Type: multipart/form-data

Step 2: Create a new block policy

1. Open the GFI WebMonitor Configuration page.
2. Navigate to Manage > Policies.
3. Click Add Policy.
4. Assign a name and description to the policy.
5. Select Block under the Allow, Block, Warn section.
6. Drag the File Types module into the right pane.
7. Click Files.
8. Click Manage File Types.
9. Enter the Content-Type found in Fiddler/Wireshark in the Content-Type field.
10. Add a description for the content file type.
11. Click the Add icon.
12. Click Files.
13. Click the  icon.
14. Select the file type created above and click Add to policy.
15. Click Save.