I have the opposite problem. The SPAM filter is turned on but fails to identify any SPAM in my inbox. It's frustrating to see so many SPAM and phishing emails. The filter is absolutely worthless. It's so bad I have decided to close down my verizon email and move my subscriptions over to my GMAIL account. Verizon still doesn't get it.
Here is a workaround I have used to combat spam with some success. It's only a workaround, not a real solution. One of the forum moderators suggested the core part of it, then I tweaked it a little. It works on the principle that most spam is sent as a BCC, and is not addressed TO the sender.
Log into webmail and go to Settings>Email settings>filters>add new filters. Set up a new rule that says "IF To: or CC:" does not contain <your email address>, then move messages to trash. I created a folder that I called "filtered spam" and have the messages moved there instead of trash so I can go back in and make sure the filters aren't catching anything I really want.
Because I use the "Always BCC myself" feature on my iPhone and iPad, I then added a second filter that says, "If From Contains <your email address>, then move messages to folder Inbox." This allows the BCC's to myself to be delivered.
The glitch is if someone legitimately sends a BCC, I don't get it. I have added several additional filters to allow some low tech newsletters that I get to be delivered. Those rules read, "If From Contains <e-mail address of the sender> Then Move messages to Inbox." It is also possible to put a domain name in the filter in lieu of an e-mail address, if you want to be certain that all BCC's from that organization come through.
This solution isn't perfect - some spam still gets through. But, over the past week, it has filtered out 450 spam e-mails and only allowed 7 spam e-mails through. Over this same period the filters caught 2 valid e-mails.
So, it's not perfect, but I find that it is still a lot better. I hope this helps.
In the meantime, let's all keep lobbying VZN for a decent spam filter.