Catching companies that give your e-mail address to spammers
The secret is to create a new e-mail address every time you open a new account or contact a company. For example, when you deal with United Airlines, you might make an address called United12345@yahoo.com. For Dell, it might be DellAddressForMe@hotmail.com.
Then, when spam comes in, you can look at the address it was sent to and know who leaked your details. If spam starts trickling in via AcmeBirdSeed3923, you'll know that it was Acme that's got the leak, since it was the only company that uses that particular e-mail address.
Creating new addresses on the free webmail services can be a lot of work, but if you're always dealing with the same few companies, you'll complete the job soon. The downside of free webmail services is that for many of them, it costs money to forward mail to your normal inbox. Yahoo Mail charges $20 a year for that. Gmail does it for free.
The solution is quicker if you have your own Web domain like I do. In that case, you can often configure your e-mail so that anything sent to your @yourwebsite.com address will wind up in the same inbox. You don't have to have your own website, only your own domain by a hosting company. There are lots of them out there. Mine charges as little as $6 a month for unlimited e-mail addresses, and others charge as little as $4 a month for 100 addresses, which is plenty for most of your day-to-day business dealings.
This method won't halt spam. Spam is the tax of the Internet. It's really only good for catching liars as they break privacy agreements with you. There's some satisfaction in being able to prove when a company that claims to be protecting your information is not doing it. You may even get some freebies if you bring it to its attention.
There are lots of ways that your e-mail address can be harvested with no one's permission. Anytime you publish it online, for example, you're open to web crawlers taking it and beating you over the head with it. But this method will at least let you know which businesses are playing dirty with your personal contact information.
If you're site-specific with the e-mail addresses you give out, you'll know who the culprits are.
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