Put an End to Cell Phone Spam

Stop E-Mail Spam From Reaching Your Smart Phone

Unlike PC-based e-mail clients such as Microsoft Outlook, most mobile e-mail clients have no way to identify and filter spam on their own. Using a Web-based filter to sort out messages before they even reach your cell phone's mail client is a great way to reduce the flow of spam.

Activate the settings through your e-mail host, usually your ISP or Web mail service. With Yahoo Mail, for example, first sign in to the Web mail site through mail.yahoo.com. Click the Options link in the upper right. Click Spam Protection to verify that Yahoo is filtering messages, and click Turn SpamGuard ON if it isn't already enabled. Other Web mail services, such as Gmail, always leave spam filtering active at the server.

If you receive e-mail through a Web host (your address looks like your_name@your_domain.com), visit the host's control panel or setup area. The specific steps may vary; contact your tech support if you need help.

In my case, I started with my host's bundled SpamAssassin instead of adding a paid alternative. I clicked the button to enable the server-side filter, and I also enabled the Spam Box option to deliver marked mail to an alternate folder. That way I can occasionally sift through those messages to identify any false positives, but they're not clogging my iPhone's e-mail inbox.

Coupled with an IMAP account, which primarily stores mail on a server instead of in a client, Spam Box saves me from downloading those messages onto my phone, though I still could do so if I wished. If you have e-mail through work, your IT department likely already uses a server-side filter similar to Spam Box; check with your IT manager if you're unsure.

Other actions can prevent junk mail from reaching your phone without involving a filter. Spammers often need your contact information to get in touch, so protect your address. When registering with a bank, cable provider, or other company, scrutinize the forms for opt-out or opt-in mailing lists to keep your address free from solicitations.

Never post your personal e-mail address online, such as in a forum; spammers can find it there to add you to lists. Even for buying things online, consider setting up a secondary e-mail address to keep your main account clean. Additionally, you could create an account exclusively for your mobile phone and be even more restrictive in sharing it than you are with your main account.

Just as they do for text messages, spammers can hit your e-mail address by sending a huge volume of messages to randomly guessed addresses at major domains. Short addresses at common domains--such as google.com, yahoo.com, or earthlink.net--are easier to guess. To reduce your chance of being victimized, use eight characters or more, including numbers and punctuation, in your address. Most of all, when you do receive spam, don't click any links inside (including any apparent "unsubscribe" links), or even load the images. Both can be ways to verify that your address is active, which will ensure that you get a whole lot more junk.

Block Sales Calls to Your Cell Phone

Telemarketing is especially annoying when it reaches your mobile phone, costing you money to hear a sales pitch. Be cautious in giving your mobile number to companies, and especially be aware of opting in or out of a company sharing or selling that information.

If you do give out a mobile number, be sure to tell companies that it's mobile. If someone calls with a pitch, ask them to take you off their list, and also mention that they have called a mobile number. It's illegal for telemarketers to use autodialers to reach mobile numbers, so they'll likely respond quickly if you let them know.

The National Do Not Call Registry can add another layer of protection, with caveats. The list is a database of numbers that telemarketers can't call, but loopholes allow calls from political groups, surveys, and companies with which you've established a business relationship. Nearly the same restrictions on sales calls apply to mobile phones already; however, if you've begun to receive sales calls on your cell phone, adding your number to the Do Not Call Registry can be the easiest way to stop them.

Zack Stern is a frequent contributor to PC World. The only thing he hates more than fingerprints on his iPhone are spam messages in his inbox.