Q: When I send out work-related e-mails, they are returned as undeliverable by Spamcop.net or Spamhaus.org.

My e-mail provider, Time Warner Cable, says the intended recipient's e-mail provider is blocking Time Warner due to the perception that spam is being sent. A Time Warner employee told me I should set up a new free e-mail account with someone such as Gmail to solve the problem.

This has been going on for about six months and I'm frustrated and furious. How can these companies block me?

Lee Schmid, Medina, OhIO

A: The problem isn't SpamCop (spamcop.net) or the Spamhaus Project (spamhaus.org), which are technology companies that help e-mail providers detect and block spam, or junk e-mail. The problem is the e-mail providers. Here's what happens:

E-mail service providers exchange mail with each other voluntarily. But this voluntary exchange often comes to a halt if "E-Mail Company A" thinks "E-Mail Company B" is sending too much spam e-mail (this can occur if Company B fails to detect and shut off e-mail accounts that are being used to send spam).

Company A decides to teach Company B a lesson by blocking B's e-mail for a while. For the duration of this blocking, everyone with an e-mail account through Company B will be unable to send an e-mail to anyone who uses e-mail from Company A.

So the Time Warner employee was correct. Time Warner e-mail is being blocked by another e-mail provider, and Time Warner can't do anything about it except search for the spammers on its network who caused the problem in the first place. Eventually the other provider will decide the lesson has been learned, and unblock e-mail from Time Warner again.

The easiest way around the blocking is to get a free Google Gmail or Yahoo Mail account. Because those e-mail providers are separate from Time Warner, they presumably aren't being blocked from reaching your intended e-mail recipients.

Q: I have quite a nice collection of music on my iPhone that I purchased through iTunes. How can I back this up on my laptop? If something happened to my iPhone, I would hate to lose my music.

Linda Lynch, Baton Rouge, La.

A: You can use iTunes on your laptop to back up content stored on your iPhone, such as music, TV shows, apps or books that have been purchased through iTunes. In addition, you can back up photos and video that you've taken with your phone, iPhone settings such as contacts or wallpaper, and other content such as ringtones.

See "iTunes: How to back up, How to restore from a backup" at tinyurl.com/37hb482. If you use Apple's iCloud online service for data backup and recovery, you'll find instructions for using it on the same page.

E-mail tech questions to steve.j.alexander@gmail.com or write to Tech Q&A, 425 ­Portland Av. S., ­Minneapolis, MN 55488. Include name, city and telephone number.