To block email attachments (outgoing email) from being sent via Gmail:

1. Log on to the TMWS console, and go to Administration > Cloud Service Filters.
2. Click the +Add button.

   

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3. Set value/option of the following fields, and then click Save:
   • Filter Name: provide a filter name
   • Select the following Request Methods:
     • POST
     • PUT
   • URLs: mail.google.com
   • Header Fields:
     • Header Field Name: x-goog-upload-command
     • Operation: Contains
     • Value: start

   

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4. Enable the filter that was created. Do the following:
   1. Go to Policies > Cloud Access Rules.
       

      You may create a new Cloud Access Rule, or use an existing policy.

       
   2. Navigate to and click the Cloud Services tab.
   3. Tick the filter that was created.
   4. Click Save.

   

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5. To test if the rule works, access Gmail account and try to attach any file. If successful, a warning similar to the sample image below will be encountered:

   

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