How to junk e-mail messages with a blank body or blank subject using Policy Filters?

To junk email with an empty message body or subject , log in to the user interface as an Admin user

Navigate Manage | Policy & Compliance | Filters | Add New Filter

1. Select Enable this Filter
2. Choose All in the conditions pull down menu.
3. Select Body from the pull down.
4. Select Matching with specific word.
5. Enter nowordsfound in the Search Value field.
6. Select Store in Junk Box for Action. 
7. Name the filter Junk Blank (can modify as needed) and save the filter.

1. Select Enable this Filter
2. Choose All in the conditions pull down menu.
3. Select Subject from the pull down.
4. Select Matching With Specific Word.
5. Enter nowordsfound in the Search Value field.
6. Select Store in Junk Box for Action
7. Name the filter Junk Blank (can modify as needed) and save the filter.

NOTE:Admin could choose "subject or body" as selected condition to trigger the policy when blank content is detected either in subject or body of the message.

NOTE: If the navigation or the screenshot looks different from the one mentioned above , you may be in an older firmware version and would require a firmware upgrade. Please refer the link below to upgrade the firmware to latest version.

https://www.sonicwall.com/en-us/support/knowledge-base/170504270079039