This are the methods from Paperclip that can be used to remove the attachments:
# Clears out the attachment. Has the same effect as previously assigning
# nil to the attachment. Does NOT save. If you wish to clear AND save,
# use #destroy.
def clear(*styles_to_clear)
if styles_to_clear.any?
queue_some_for_delete(*styles_to_clear)
else
queue_all_for_delete
@queued_for_write = {}
@errors = {}
end
end
# Destroys the attachment. Has the same effect as previously assigning
# nil to the attachment *and saving*. This is permanent. If you wish to
# wipe out the existing attachment but not save, use #clear.
def destroy
clear
save
end
So you see, destroy only removes the attachment if no error occurs. I have tried it with my own setup against S3 so I know that destroy works.
Could the problem in your case possible be that you have any validations that cancels the save? I.e validates_attachment_presence or something similar?
I think one way to find out would be to try @user.logo.destroy and then check the content of @user.errors to see if it reports any error messages.