You receive error 0x80070020 when you use the Windows Update Web site or the Microsoft Update Web site to install updates

When you try to download an update from Windows Update Web site or from the Microsoft Update Web site, you receive an error message that tells you that the process cannot access the update file because it is being used by another process. This article contains step-by-step methods that you can use to resolve this issue and successfully download Windows updates.

This article is intended for a beginning to intermediate computer user.You may find it easier to follow the steps if you print this article first.

When you try to download an update from the Windows Update Web site or from the Microsoft Update Web site while you are using Windows XP or Windows Vista, you receive the following error message: Additionally, you may receive the following error message.

This issue can occur because of a timing issue that occurs when you try to download the update. Or, it can occur if a program is interfering with the automatic update process. For example, antivirus programs that use real-time scanning can interfere with the automatic update process.

Problems with installing Windows updates can occur when Windows Update and another program both try to access the same file. Although many programs can cause this issue to occur, the most common are antivirus programs and programs that perform real-time backups of system files.

This section contains several methods that may help you resolve the problem. Complete the steps in each method, and then try again to install the updates. If the issue is not resolved, go to the next method and complete those steps before trying to install the updates again.

Method 1: Restart your computer, and install the updates

Close all programs that are running, and then restart your computer. After the computer has started successfully, look in the notification area in the lower-right side of the screen for the Windows Update icon. If the icon is available, double-click it, and then install any available updates. If icon is not available, click Start, click All Programs, and then select Windows Update from the list of applications.

Method 2: Start the computer in safe mode with network support, and then install the updates

Windows 2000, Windows XP or Windows Server 2003

To start the computer in safe mode in Windows 2000, in Windows XP, or in Windows Server, follow these steps:

1. Restart your computer and start pressing the F8 key on your keyboard.
2. In the Windows Advanced Options menu, click Safe mode with networking (SAFEBOOT_OPTION=Network), and then press ENTER.
   
   Note This option starts Windows in safe mode and includes the network drivers and services that are needed to access the Internet or to access other computers on your network are included. The Safe mode with networking option does not work for computers that have dial-up connections to the Internet. You cannot use safe mode with networking support because modem drivers and PC Card drivers do not load in Safe mode with networking support.
3. Install the updates.
4. After the updates are installed, restart your computer in safe mode, and then select Start Windows Normally.
   
   Note This option starts Windows in its normal mode.

If these steps do not resolve the issue continue to method 3.

Windows Vista or Windows Server 2008

To start your computer in safe mode in Windows Vista or in Windows Server 2008, 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.
   
   Note The Safe mode with networking option does not work for computers that have dial-up connections to the Internet. You cannot use safe mode with networking support because modem drivers and PC Card drivers do not load in safe mode with networking support.
5. In the System Configuration dialog box, click Restart. The computer restarts in "Safe mode with networking" mode.
6. Install the updates.
7. After the updates are installed, restart your computer in safe mode, and then click to clear the Safe boot check box.
8. In the System Configuration dialog box, click Restart. This option starts Windows in its normal mode.

If these steps do not resolve the issue continue to method 3.

This section is intended for advanced computer users. If you are not comfortable with advanced troubleshooting, you might want to ask someone for help or contact support. For more information about how to contact Microsoft support, visit the following Microsoft Web site:

Method 3: Perform a clean boot of the computer and then install the update

To perform a clean boot of the computer, follow the appropriate steps for your version of Windows.

Windows 2000, Windows XP, or Windows Server 2003

To manually perform a clean boot of your computer in Windows 2000, Windows XP, or Windows Server 2003, follow these steps:

1. Click Start, click Run, type msconfig, and then click OK.
2. On the General tab, click Selective Startup, and then click to clear the following check boxes:
   • Process SYSTEM.INI File
   • Process WIN.INI File
   • Load Startup Items
3. On the Services tab, click to select the Hide All Microsoft Services check box, and then click Disable All.
4. Click OK, and then click Restart to restart your computer.
5. Run Microsoft Update or Windows Update. If the update does not run successfully, go to Method 4.

Windows Vista or Windows Server 2008

To manually perform a clean boot of the computer in Windows Vista or Windows Server 2008, follow these steps:

1. Click Start
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   , type msconfig in the Start Search box, and then press ENTER.
   
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   If you are prompted for an administrator password or for a confirmation, type the password or click Continue.
2. On the General tab, click Selective startup.
3. Under Selective Startup, click to clear the Load startup items check box.
4. Click the Services tab, click to select the Hide All Microsoft services check box, and then click Disable all.
5. Click OK, and then click Restart.
6. Run Microsoft Update or Windows Update. If the update does not run successfully, go to Method 4.

Note For more information about performing a clean boot, click the following article number to view the article in the Microsoft Knowledge Base:

Method 4: Temporarily disable spyware and antivirus software

Warning This workaround may make a computer or a network more vulnerable to attack by malicious users or by malicious software such as viruses. We do not recommend this workaround but are providing this information so that you can implement this workaround at your own discretion. Use this workaround at your own risk.

To disable your antivirus or antispyware software, follow these steps:

1. Locate your antivirus or antispyware icon in the notification area. You can find the notification area at the lower-right of your screen in the taskbar area near the clock. The notification area displays the icons of the programs that you are currently running. When you move your pointer over the icons, Windows displays the name of the program.
2. Right-click your antivirus or antispyware icon, and then select Disable Auto-Protect. A red "X" should appear over the icon in the notification area to show that the application is now disabled.
   
   Note Antivirus and antispyware programs differ in how they work. If these steps did not help you disable your program, you may want to contact your antivirus program's Help system for steps that you can use to do this task. You can usually also find the steps for your antivirus program on the Internet. To find them, type "disable virus scan" and then the name of your antivirus program in your favorite search engine, and then click Search.
3. Run Microsoft Update or Windows Update.
4. Turn on (re-enable) your antivirus or antispyware program. To do this, right-click your antivirus or antispyware icon in the notification area, and then click Enable. Antivirus and antispyware products protect your systems from computer viruses and malicious attacks. Because new viruses are created every day and your system is susceptible at any time, it is important to keep your antivirus and antispyware products enabled, or turned on.

Method 5: Temporarily disable any firewalls

Warning This workaround may make a computer or a network more vulnerable to attack by malicious users or by malicious software such as viruses. We do not recommend this workaround but are providing this information so that you can implement this workaround at your own discretion. Use this workaround at your own risk.

Disable the Windows Firewall in Windows 2000, Windows XP and Windows Server 2003

To temporarily disable Windows Firewall in Windows 2000, Windows XP, and Windows Server 2003, follow these steps:

1. Click Start, click Run, type Firewall.cpl, and then click OK.
2. On the General tab, click Off (not recommended), and then click OK.
3. Run Microsoft Update or Windows Update.

Note Remember to turn Windows Firewall back on. A firewall helps protect your computer from attack by malicious users or by malicious software. Malicious software includes viruses that use unsolicited incoming network traffic to attack your computer.

Disable Windows Vista or Windows Server 2008 Firewall

To temporarily disable the firewall in Windows Vista, follow these steps:

1. Click Start
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   , and then click Control Panel.
2. Click Security, and then click Windows Firewall.
3. Click Turn Windows Firewall on or off.
4. In the Windows Firewall Settings window, click Off (not recommended), and then click OK.
5. Run Microsoft Update or Windows Update.

Note If you are running a third-party firewall program, see your program's documentation for more information about disabling your firewall program.

Remember to turn your firewall back on. A firewall helps protect your computer from attack by malicious users or by malicious software. Malicious software includes viruses that use unsolicited incoming network traffic to attack your computer.