1. Login to your Gmail Account, Then go to "Settings" tab
2. Under Settings we have "Filters" tab, select a "Create New Filter"
3. Then a new window appears in that we have "Has the Words" box, in that type "in:spam", then click on the "Next step"
4. Then Tick "Delete it" and tick "Also Apply filter to 0 matching conversations"
5. Then click "Create Filter"
That's all you are done...!!!
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