How to troubleshoot compatibility problems that affect Internet Explorer 7 in Windows Vista

This article describes how to troubleshoot software compatibility problems that affect Windows Internet Explorer 7. To help determine which program may be causing the problem, you can take the following steps:

1. Use safe mode with networking
2. Perform a clean boot
3. Use a different user account
4. Scan your computer for viruses and spyware
5. Run Internet Explorer 7 in "No Add-Ons" mode

Step 1: Use safe mode with networking

To determine whether the problem is related to software compatibility, test Internet Explorer in safe mode with networking. Safe mode is a way of running Vista with a minimal set of device drivers, programs, and services. Safe mode is usually used for troubleshooting.

Note If the following conditions are true, you cannot use safe mode with networking:

• You connect to the Internet by using a PPPoE connection. (Most DSL connections use PPPoE.)
• The PPPoE connection requires a username and a password.
• The computer is connected directly to a DSL modem. (If you connect to the Internet by using a router that is connected to a DSL modem, you can use safe mode with networking.)

If you cannot use safe mode with networking, go to step 2.

To start the computer in safe mode with networking, follow these steps:

1. Click Start
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   , and then type msconfig in the Start Search box.
2. In the Programs section, click Msconfig.exe.
3. In the System Configuration dialog box, click the Boot tab.
4. Click to select the Safe boot check box, click Network, and then click OK.
5. In the System Configuration dialog box, click Restart.

The computer restarts in safe mode with networking. Test Internet Explorer to determine whether the problem still occurs. If the problem does not occur, a service or a program may cause compatibility problems when the computer starts as usual. In this situation, restart the computer in normal mode. Then, go to step 2. To restart the computer in normal mode, follow these steps:

1. Click Start
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   , and then type msconfig in the Start Search box.
2. Under the Programs section, click Msconfig.exe.
3. In the System Configuration dialog box, click the Boot tab.
4. Click to clear the Safe boot check box, and then click OK.
5. In the System Configuration dialog box, click Restart.

If you cannot connect to the Internet when the computer is in safe mode with networking, there may be a problem with the network adapter. For more information about connectivity problems in Windows Internet Explorer 7, click the following article number to view the article in the Microsoft Knowledge Base: For more information about safe mode for Windows Vista, visit the following Microsoft Web site:

Step 2: Perform a clean boot

By starting the computer so that it uses a minimal set of drivers and startup programs, you can help determine whether a program is interfering with Internet Explorer or whether a program is causing a problem with your Internet connection. This kind of startup is known as a "clean boot." For more information about this method of troubleshooting, click the following article number to view the article in the Microsoft Knowledge Base: Note Before you disable any third-party services, we recommend that you make sure that Windows Firewall is enabled. If Windows Firewall is not enabled, the computer may be left in a vulnerable state.

After you perform "clean boot" troubleshooting, test Internet Explorer to determine whether the problem still occurs. If the problem still occurs, go to step 3.

Step 3: Use a different user account

To determine whether the problem is related to your user account, use a different user account to test Internet Explorer. If you do not already have another account on the computer, follow these steps to create a new account:

1. Click Start, and then click Control Panel.
2. In the search box, type User Accounts.
3. In the details pane, double-click User Accounts, and then click Manage another account.
   
   
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   If you are prompted for an administrator password or for a confirmation, type the password, or click Continue.
4. On the Choose the account that you would like to change page, click Create a new account.
5. Follow the steps in the wizard to create a new account. For troubleshooting, we recommend that you grant administrative credentials to the new account.

After you create the new account, log off the computer. Then, use the new account to log on. If the problem does not occur when you use the new account, you can migrate the data and the settings from the old account to the new account. For more information about how to do this, click the following article number to view the article in the Microsoft Knowledge Base: If the problem still occurs, go to step 4.

Step 4: Scan your computer for viruses and spyware

To determine whether malicious software has infected your computer, scan your computer by using both antivirus software and antispyware software. Windows Vista includes an antispyware program that is named Windows Defender. However, you must obtain your own antivirus program.

For information about how to use Windows Defender to remove malicious software, visit the following Microsoft Web site:For information about how to help protect the computer from viruses, visit the following Microsoft Web site:If the problem still occurs, go to step 5.

Step 5: Run Internet Explorer 7 in "No Add-Ons" mode

If the problem still occurs after you complete steps 1 through 4, an add-on or a toolbar may be causing the problem in Internet Explorer. Run Internet Explorer 7 in "No Add-Ons" mode. For more information about how to do this, see method 3 in the following Microsoft Knowledge Base article: