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More dire warnings seem to come with every passing digital day.

Google begins alerting Gmail users that foreign governments may be trying to hack their accounts. LinkedIn, eHarmony, and Lastfm announced that they have had millions of user passwords exposed online by hackers looking to make a buck. And then there's the government sponsored attacks, such as Stuxnet and Flame.

The message is clear: Start protecting yourself.

This isn't Smokey the Bear advice: You can't prevent determined hackers from breaking into LinkedIn or eHarmony. But you can take preventative measures to protect yourself—whether you're looking to protect your online reputation for professional reasons or just want to guard against digital burglars.

First and foremost, make your e-mail password the toughest most convoluted phrase of letters and number you can think of, and use it only for e-mail. This is your first line of defense since many services will e-mail you when someone tries to change your other accounts.

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Second, protect your smartphone. These handheld devices now contain more important and personal information than a desktop computer and are infinitely more liable to theft or loss. The founder of a computer security firm recently recounted to me how his phone was stolen while he was talking on it. Using an old pickpocket trick, one crook bumped him to distract his attention while the other smoothly snatched the phone, ran around the corner, and removed the SIM card before he could have remotely wiped. All his information, personal and professional was potentially vulnerable.

To combat theft, some apps take advantage of the technology available on the handset to foil thieves. There are at least two programs will a nifty trick: every time someone unsuccessfully tries to enter your phone's password (you are using password protection, right?) the phone will take a picture of the culprit using the front facing camera and then store and e-mail the photo to you. It can perform this legerdemain without activating the camera light and alerting the thief.

'Information about you can show up in more than a dozen of Google's other search services.'

— Online privacy firm attorney Sarah Downey

GotYa, $1.99 for Android phones, will also mark the location of your device and time stamp the image so you know where and when the criminal had your phone. And it's not only handy for stolen phones. It's great for office workers who suspect others are trying to access their phone when they leave it unattended. A colleague recently showed me such a picture of a co-worker trying to gain entry to his phone. Now he'll never trust that fellow again.

Going a few steps further is NQ Mobile Vault by storing messages, contacts, and photos under another layer of password protected encryption. The premium version of the app is $1.99 a month for Android phones and can be concealed so that it does not appear in your application screens. The truly paranoid can even set up “fake” vaults, so that if someone, say, an employer, insists on access to your phone, you can show them the fake vaults.

Those looking for a job—and there are plenty of us out there—should pay particular attention to digital security. Your personal details about you online could blow a great interview and perfect resume, warns Sarah Downey, an attorney at online privacy firm Abine.

“Information about you can show up in more than a dozen of Google's other search services, such as Images, Videos, Blogs, Groups, and News,” Downey warns. So do a thorough search before you begin the job search. Also look for any terms related to you that might call up negative results. “If you have an arch-nemesis out there who's a blogger, you may want to search for your name alongside that person's name,” she says.

Finally, go on a defriending spree (quietly), says Downey, and clean up your Facebook feed. Low-cut blouses and beer photos are definitely out. She also warns that an increasing number of potential employers routinely send friend requests to prospects. And what are you going to do when you receive such a message?

If all this seems like too much trouble, you can put it in the hands of a professional Abine offers a service, for example, that will look for personal information about you online and “cut through the red tape” of having details like your address and phone number removed from sites around the Web.

It's essentially an online scrubbing service, but the DeleteMe service will cost you to keep clean: $99 a year. On the other hand, if you're looking for a job it might just be worth it.

Follow John R. Quain on Twitter @jqontech or find more tech coverage at J-Q.com.