Answer Line

I Can't Open Files of a Particular Type

Windows uses a file's extension (.xls, .docx, .mp3, and so on) to know what program should open it. But if the extension isn't associated with a particular application, Windows has no idea what to do with it.

Here's how to make that association in Windows 7, XP, and Vista:

3

Put a Second Windows Environment on Your PC

There are several ways to set up a second Windows environment on your primary computer. But let me start with one that doesn't work: You can't install Windows on an external drive and boot from that. Windows only works from an internal drive.

But here are a few things you can do:

9

Clean Up Explorer's Context Menu

The right-click context menu is one of Windows' best innovations (although Borland invented that feature years before Microsoft). But it can get out of hand. When I right-click a file, I get 25 options. Six of those are submenus filled with more options.

2

Can Anything Replace iGoogle?

I recommend NetVibes, even it can be a little intimidating at first. It asks you to pick or type a subject, and then it overloads you with four or five tabs filled with a great many widgets. But there's an easy if not obvious way to skip all that and built your own modest or ambitious home page.

But I should point out that tabs are one of NetVibes' best features. You can create tabs based on topics (Tech, Entertainment, and so on), types of information (news feeds, videos), or any other way that you can think of. When you search Google from NetVibes, the results appear in a new tab.

11

Remove an Unwanted Email Address in Outlook

Outlook, like Gmail, offers an interesting convenience that can sometimes turn into a problem. If you send a message to someone who is not listed amongst your contacts, Outlook remembers the email address. When you start typing an address or name in the To field of an email, these unlisted addresses (sorry, I couldn't resist) pop up, along with those in your address book. This allows you to easily bring up someone's address without bothering to first enter it into Outlook's Contacts database.

But these unofficial addresses can also be annoying. If an out-of-date email address--or worse, an out-of-favor friend--pop up when you don't want it to, you might not consider it all that convenient.

5

Read Old Outlook Express Messages When You No Longer Have Outlook Express

For many years and versions, Windows came with the Outlook Express email program. Microsoft discontinued Outlook Express with Vista, which had its own email program--Windows Mail. Windows 7 lacks a bundled email program, but you can download and install Microsoft's free Windows Live Mail. Many PCs come with it pre-installed.

Outlook Express saved messages in .dbx files, with each file containing the contents of an Outlook Express folder. In other words, all of the messages in your inbox would reside in inbox.dbx. If you created another folder called To Do Later, the messages you saved there would be stored in To Do Later.dbx.

5

My Twitter Account Has Been Hacked!

If you appear to be sending tweets and/or direct messages that you haven't actually sent, your Twitter account has been hacked. Here's what you need to do:

First, try to log onto Twitter. If you succeed, change your password immediately. Here's how:

1