It was the incentive -- a $200 gift card -- that prompted Bob DuScheid of Baldwin Borough to continue with Comcast as his Internet, television and phone service provider.

Mr. DuScheid, 69, a retired AT&T communications technician, called Comcast in February and asked a customer service representative if he could renegotiate his agreement to save some money.

She said yes and, after some discussion, lowered his monthly bill from $215 to $175, an annual savings of $480. She then said the company would send him a $200 gift card if he agreed to a two-year contract. Mr. DuScheid accepted the offer.

But the gift card never arrived.

After waiting more than three months, he called Comcast. A supervisor said the company had made a mistake in offering the gift card. She said he wouldn't be receiving one. She said he should have received a postcard saying the offer had been withdrawn.

Mr. DuScheid hadn't.

And he wasn't happy with Comcast's now-you-have-it, now-you-don't offer.

"That 'sorry, we screwed up' is not an acceptable response," he said. "I have a copy of the agreement, which I signed in good faith, and returned the original to them. Am I simply out of luck?"

No.

I relayed Mr. DuScheid's e-mail to Comcast spokesman Bob Grove. He forwarded it to the appropriate department.

Mr. DuScheid said a customer service representative contacted him last week, apologized for the withdrawn offer and said she would give him a $200 credit on his Comcast bill because she didn't have the authority to issue a gift card.

"I accepted her offer," he said.

It pays -- literally, in this case -- to keep a copy of any and all such offers from companies. "Let-us-do-it-all-for-you" communication packages cost consumers thousands of dollars by locking them into multi-year contracts. And if you want out early, you have to pay a penalty.

Because postcards can get caught up in bulk mail items such as advertising circulars -- which recipients may discard without paging through them -- Comcast could have used something other than a postcard to notify Mr. DuScheid that it had withdrawn its gift card offer.

It does, after all, have his phone number and e-mail address.

Linda Criddle, president of the Safe Internet Alliance, would like to share some of the things she's learned while interviewing criminals as part of her work to protect Internet users.

She has outlined the tips in "11 Things An Online Criminal Will Never Tell You." Some of the information should be second nature to all computer users: strong passwords -- those that use a combination of numbers and letters -- "really are your best friend," up-to-date security software "is critical to blocking out identity theft, robberies and other real-world crimes," and watch what you share.

Here are some things Ms. Criddle says you may not know.

"Lots of identity theft and home robberies are done by people you, or family members, know."

Criminals exploit bridal and baby registry websites. They can see what has been purchased and when it will arrive. The types of gifts requested "shows your economic status ... When you include a blog in your registry, you typically [reveal] when you will be away from home on that honeymoon or at the hospital. Use a site that allows you to set privacy boundaries."

"Keep photos of family, friends, possessions and homes private," she said. Photos can disclose your approximate age, socioeconomic status, possessions, home, friends and more. Criminals can use that information "to customize spam and scams, break into your home, know what to steal, take your identity or threaten a family member."

For more information, go to www.safeinternet.org.

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