Since last few months Norton Internet Security not stopping spam e-mail

I am using Norton Internet Security Version 22.7.0.76 (Japanese).

I am asking question here may be someone could guide me.

Actually I am very old Norton user and very sad to say since last few months specially the last update Norton is not stopping spam e-mail as it had been doing before. Right now I got 323 almost same e-mail with attachments. As Norton did not do anything I got to access from server and deleted the spam messages from server as well as on computer.

I have also read about Norton Security flaw does this mean this product is not fine any more and I should use another?Anyone just tell me why Spam E-mails are not landing in the Spam folder rather coming in Inbox.

Note: Norton is update. OS: Windows Vista 32 bit (will move to Windows 10 sooner)

Thank you in advance.