"The Windows Installer service could not be accessed" error message when you try to install Office

When you try to install Microsoft Office, you may receive an error message that is similar to the following:

This problem may occur if the Windows Installer files are damaged or missing.

To resolve this problem, use one of the following methods.

Method 1: Use the Msconfig tool to confirm that the installer service is running

1. Click Start, and then click Run.
   
   
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2. In the Open box, type msconfig, and then click OK.
   
   
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3. On the Services tab, click to select the check box that is next to Windows Installer .
   
   
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4. Click OK, and then click Restart to restart the computer.
   
   
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5. Install Office again. When you are prompted to enter the product key, type the product key, and then click Next.

Office will be installed, and you will not be prompted for the product key when the programs start.

Method 2: Re-register Windows Installer

Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:

Note Because there are several versions of Microsoft Windows, the following steps may be different on your computer. If they are, see your product documentation to complete these steps.

To re-register Windows Installer, follow these steps.

Note If you cannot complete the following steps, go to method 3.

1. Click Start, and then click Search.
   
   
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2. Click All files and folders.
   
   
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3. In the File name box, type Msiexec.exe, and then click Search.
   
   
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4. After the search is complete, make a note of the location of the Msiexec.exe file. The location of the file should be similar to the following example:
   C:\Windows\System32
   
   
   
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5. On the File menu, click Close to close the Search dialog box.
   
   
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6. Click Start, and then click Run.
   
   
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7. In the Open box, type regedit, and then click OK.
   
   
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8. Locate and then click the following registry key:
   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSIServer

   
   
   

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9. In the right pane of the Registry Editor window, double-click ImagePath.
   
   
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10. In the Edit String dialog box that appears, make sure that the string in the Value data box contains the correct path for the Msiexec.exe file that you determined in step 4.
    
    Note The following is an example of the correct path, where drive is the drive where Windows is installed:
    drive :\Windows\System32\msiexec.exe /V
    
    
    If the Value data box does not contain the correct path, make changes to correct the path, and then click OK to close the Edit String dialog box.
    
    
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11. On the File menu, click Exit to quit Registry Editor.
    
    
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12. Start your computer in Safe mode, and then register the Msiexec.exe file. To do this, follow these steps:
    1. Shut down your computer, and then restart your computer.
    2. Restart your computer and press the F8 key on your keyboard. On a computer that is configured for booting to multiple operating systems, press the F8 key when you see the Boot menu.
    3. Use the ARROW keys to select Safe Mode, and then press ENTER.
    4. If the Boot menu appears again, and the words "Safe Mode" appear in blue at the bottom, select the installation that you want to start, and then press ENTER.
    5. Log on to the computer.
    6. Click Start, click Run, type msiexec /regserver in the Open box, and then click OK.
       
       
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13. Shut down your computer, and then restart your computer normally.

If you still cannot install Microsoft Office successfully and you receive an error message that is similar to the message listed in the "Symptoms" section, go to Method 3.

Method 3: Try the methods that are listed in Microsoft Knowledge Base Article 319624

Try the methods that are listed in the following Microsoft Knowledge Base article:

Method 4: Reinstall Windows Installer

Note This method applies to Microsoft Windows 95, Microsoft Windows 98, Microsoft Windows Millennium Edition (Me), and Microsoft Windows NT 4.0. For Microsoft Windows 2000, Microsoft Windows XP, and Microsoft Windows Server 2003, either reapply the latest service pack or repair the operating system.

To reinstall the Windows Installer, follow these steps.

1. Click Start, and then click Run.
   
   
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2. In the Open box, type cmd, and then click OK.
   
   
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3. At the command prompt, type the following lines. Press ENTER after you type each line.
   cd %windir%\system32
   
   

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   ren msi.dll msi.old
   
   

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   ren msiexec.exe msiexec.old
   
   

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   ren msihnd.dll msihnd.old
   
   

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4. At the command prompt, type exit, and then press ENTER.
   
   
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5. Restart your computer.
6. Update the Windows Installer files to the latest version. To do so, visit one of the following Microsoft Web sites, and then download and install Windows Installer 2.0.
   
   Note Windows Installer 2.0 is included with Microsoft Windows XP. You do not have to perform this step if you are using Windows XP.
   • For Windows 98, Windows 98 Second Edition, and Windows Millennium Edition:
     http://www.microsoft.com/downloads/details.aspx?FamilyID=cebbacd8-c094-4255-b702-de3bb768148f%20&displaylang=en

     (http://www.microsoft.com/downloads/details.aspx?FamilyID=cebbacd8-c094-4255-b702-de3bb768148f%20&displaylang=en)
   • For Microsoft Windows NT 4.0 and Microsoft Windows 2000:
     http://www.microsoft.com/downloads/details.aspx?FamilyID=4b6140f9-2d36-4977-8fa1-6f8a0f5dca8f&DisplayLang=en

     (http://www.microsoft.com/downloads/details.aspx?FamilyID=4b6140f9-2d36-4977-8fa1-6f8a0f5dca8f&DisplayLang=en)
7. After the installation of the Windows Installer is complete, shut down and restart your computer normally before you install Microsoft Office.

For more information about how to restart Windows in Safe mode, click the following article numbers to view the articles in the Microsoft Knowledge Base: For more information about how to obtain the Windows Installer, click the following article number to view the article in the Microsoft Knowledge Base: