Why am I being re-directed to Bing?

It sounds like you might have installed malware or adware on your computer. Download and run Malwarebytes Anti-Malware for Mac. It was developed by a trusted and respected contributor here. After you run it and do whatever it asks you to do, open Safari and type a search term in the address bar. Are you still redirected to Bing?

Don't use any kind of "anti-virus" or "anti-malware" product on a Mac. There is never a need for it, and relying on it for protection makes you more vulnerable to attack, not less.

You installed one or more variants of the "InstallMac" trojan. Please take the steps below to disable it.

The criminal behind this attack tries to make the malware hard to remove by varying the names of the files it installs. This procedure works as of now, as far as I know. It may not work in the future. Anyone finding this comment a few days or more after it was posted should look for a more recent discussion, or start a new one.

Back up all data before continuing.

1. Triple-click the line below on this page to select it, then copy the text to the Clipboard by pressing the key combination command-C:

~/Library/LaunchAgents

In the Finder, select

Go ▹ Go to Folder...

from the menu bar and paste into the box that opens by pressing command-V. You may not see what you pasted because a line break is included. Press return. A folder named "LaunchAgents" will open.

2. Inside the folder you just opened, there may be files with a name of any of these forms:

something.AppRemoval.plist

something.download.plist

something.ltvbit.plist

something.update.plist

Here something is usually a meaningless string, such as any of the following:

Epolife

InstallMac

Javeview

Kuklorest

Manroling

Otwexplain

These are examples, not a complete list. The string could be anything. The point is that the same string will usually appear in the name of three or four files.

Lately, the "InstallMac" attacker has been scrambling the strings "AppRemoval," "download," "ltvbit," and "update" in the names of his files. For example, you might see file names such as these, instead of the above:

something.AppVemoral.plist

something.dolnwoad.plist

something.btvlit.plist

something.uadpte.plist

You could have more than one copy of the malware, with different values of something.

Move all such items to the Trash. If there are any other files with a name that begins with something, move those to the Trash also. After you've done that, there may not be anything left in the LaunchAgents folder; in that case, you can delete the folder, but otherwise don't delete it. Other files in the folder are not necessarily malicious (though they could be, if you also installed some other kind of malware.)

Log out or restart the computer. The trojan should now be inactive.

3. This step is optional. Open the following folder as in Step 1:

~/Library/Application Support

and move to the Trash any subfolders with the name something that you found in Step 2.

Don't move the Application Support folder or anything else inside it.

4. Open the Applications folder. If there is an item named something, or "Zip Devil," or with any of the other names listed in Step 2, drag it to the Trash.

If in doubt, press the key combination option-command-4 to arrange the apps by date added. Look at the apps that have been added since you first noticed the problem. If there is one you don't recognize, drag it to the Trash.

You may get an alert that the item is locked. Confirm that you want to move it to the Trash.

Empty the Trash.

If you get an alert that the application is in use, force it to quit.

5. From the Safari menu bar, select

Safari ▹ Preferences... ▹ Extensions

Uninstall all extensions you don't know you need. If in doubt, remove all of them. None is required for normal operation. Do the equivalent in the Chrome and Firefox browsers, if you use either of those.

If the Preference window won't open, restart the computer in safe mode. Certain caches maintained by the system will be rebuilt.

6. Reset the home page in each of your browsers, if it was changed. In Safari, first load the home page you want, then select

Safari ▹ Preferences... ▹ General

and click

Set to Current Page

I must admit that I'm very nervous to do this.

There's no need to be. The procedure is perfectly safe.

Why oh why do these things happen?

They happen when you download unknown software that you don't need, merely because some stranger on a website tells you to. If you don't do that, you'll be safe from malware attack.

As I wrote earlier, there are (potentially) three folders of which you should post screenshots. Some of them may not exist. If the instructions are unclear, please specify what you don't understand.

That's fine. Any more?

No, not everything. Leave the first row alone and delete everything in the second and third rows. Then log out or restart the computer.

It's important that you avoid having this kind of thing happen again.

Until you have more experience as a Mac user, I suggest that you change a setting to allow only Apple updates and software from the App Store to be installed.

Open the Security & Privacy pane in System Preferences and select the General tab. Click the lock icon in the lower left corner and enter your password to unlock the settings. Select the button marked

Mac App Store

and close the preference pane. For information about the effects of the setting, see this support article. You may need to change the setting temporarily to install some third-party software, such as Adobe Flash Player. Be especially careful with that, as malware is often distributed in the form of a fake Flash update. Never follow a link to a Flash update on any web page. Instead, use the built-in updater in the Flash Player preference pane.

The products in the App Store, while they aren't always very good, can at least be considered safe enough to use.