How to manually remove and then reinstall the.NET Framework 2.0

This step-by-step article describes how to troubleshoot issues that you may experience when you install the .NET Framework 2.0.

When Microsoft Windows Installer is incorrectly registered in the Windows registry, the .NET Framework 2.0 Setup program cannot access some Windows Installer components. This article discusses how to work around this issue by unregistering and then reregistering Windows Installer.

You may not always be able to completely remove the .NET Framework 2.0 by using the Add/Remove Programs tool in Control Panel. This article also discusses how to work around this issue either by repairing the .NET Framework 2.0 or by manually removing the .NET Framework 2.0 from the computer and then reinstalling the .NET Framework 2.0.

Requirements

The following list outlines the recommended hardware, software, network infrastructure, and service packs that you need:

• Microsoft Windows Server 2003, Microsoft Windows 2000 Service Pack 3 (SP3), or Microsoft Windows XP Service Pack 2 (SP2)
• Microsoft .NET Framework 2.0.
  To obtain the Microsoft .NET Framework Version 2.0 Redistributable Package, visit the following Microsoft Web site: 

  Microsoft .NET Framework Version 2.0 Redistributable Package (x64)

Note To troubleshoot .NET Framework 2.0 installation issues, you must use an account that is in the Local Administrators group on the computer that is running the .NET Framework 2.0.

This article assumes that you are familiar with the following topics:

• Microsoft .NET Framework 2.0
• Registry Editor
• Windows Installer

Unregister and then reregister Windows Installer

This action corrects most situations. Additionally, this action does not affect any currently installed programs that use the Windows Installer.

1. Unregister Windows Installer. To do this, click Start, click Run, type msiexec /unregister in the Open box, and then click OK.
2. Reregister Windows Installer. To do this, click click Start, click Run, type msiexec /regserver in the Open box, and then click OK.

Repair the .NET Framework 2.0

The following are three ways to repair the .NET Framework.

Use the Repair command on the Windows Installer cache file

To repair the .NET Framework 2.0 by using the Windows Installer cache file, follow these steps:

1. Click Start, click Run, type installer in the Open box, and then click OK.
2. On the View menu in Windows Installer, click Details, right-click the Name column header, and then click Comment.
3. Right-click the cached Windows Installer file that has the Microsoft .NET Framework 2.0 RTL x86 enu comment, and then click Repair.
4. After the repair process has completed, quit Windows Installer.

Run the .NET Framework 2.0 Redistributable package at a command prompt

To repair the .NET Framework 2.0 by using the command prompt, follow these steps:

1. Locate the Dotnetfx.exe file that you used to install the .NET Framework 2.0. To do this, use one of the following methods:
   • If you installed the .NET Framework 2.0 from a CD or from a DVD, insert the installation disk in the CD drive or DVD drive.
   • If you installed the .NET Framework 2.0 from the hard disk, download the .NET Framework 2.0 Setup program to the hard disk.
   • If you installed the .NET Framework 2.0 from a network drive, reconnect to the network drive.
2. Click Start, click Run, type cmd in the Open box, and then click OK.
3. At the command prompt, run the following command:
   %InstallationPath%\dotnetfx.exe /t:%temp% /c:"msiexec.exe /fvecms %temp%\netfx.msi"

Manually remove and then reinstall the .NET Framework 2.0

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:

Important These steps may increase your security risk. These steps may also make your computer or your network more vulnerable to attack by malicious users or by malicious software such as viruses. We recommend the process that this article describes to enable programs to operate as they are designed to, or to implement specific program capabilities. Before you make these changes, we recommend that you evaluate the risks that are associated with implementing this process in your particular environment. If you choose to implement this process, take any appropriate additional steps to help protect your system. We recommend that you use this process only if you really require this process.

1. Remove the .NET Framework 2.0 from the Windows Installer cache:
   1. Click Start, click Run, type installer in the Open box, and then click OK.
   2. On the View menu in Windows Installer, click Details.
   3. Right-click the Name column header, and then click Comments.
   4. Right-click the cached Windows Installer file that has the Microsoft .NET Framework 2.0 RTL x86 enu comment, and then click Uninstall.
   5. After the uninstall process has completed, quit Windows Installer.
2. Manually delete the following from the computer. Note Depending on the current condition of the .NET Framework installation, these items may not exist on the computer.
   • The URTTemp folder
   • The Mscoree.dll file
   • The v2.0.50727 folder
   To do this, follow these steps:
   1. Click Start, click Run, type system32 in the Open box, and then click OK. The contents of the System32 folder appear in Windows Explorer.
   2. Locate and then delete the URTTemp folder.
   3. Locate and then delete the mscoree.dll file.
      
      Note If the .NET Framework 1.1 or the .NET Framework 1.0 is also installed on the computer, and you do not intend to reinstall the .NET Framework 2.0, you must repair the .NET Framework 1.1 or the .NET Framework 1.0. For more information, see the "Repair the .NET Framework" section of the following Microsoft Knowledge Base article:
      824643 How to troubleshoot Microsoft .NET Framework 1.1 installation issues in Windows XP or in Windows 2000
   4. Click Start, click Run, type microsoft.net in the Open box, and then click OK. The contents of the Microsoft.NET folder appear in Windows Explorer.
   5. In the Microsoft.NET folder, double-click the Framework folder.
   6. In the Framework folder, delete the v2.0.50727 folder.
   7. Close the Framework folder.
3. Manually delete the relevant registry keys:
   1. Click Start, click Run, type regedit in the Open box, and then click OK to start Registry Editor.
   2. In Registry Editor, locate and then delete the following registry keys.
      
      Note Depending on the current condition of the .NET Framework installation, these registry keys may not exist on the computer.
      • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v2.0.50727
      • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\policy\v2.0
   3. Quit Registry Editor.
4. Use the Windows Installer CleanUp Utility (Msizap.exe) to remove Windows Installer information from the registry. The components (Msizap.exe) of the Windows Installer Software Development Kit are included in the Microsoft Windows Software Development Kit (SDK).
   
   The following file is available for download from the Microsoft Download Center:
   Download the Windows Installer CleanUp Utility (Msicuu2.exe) package now.
   For more information about how to download Microsoft support files, click the following article number to view the article in the Microsoft Knowledge Base:
   119591 How to obtain Microsoft support files from online services
   Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help prevent any unauthorized changes to the file.
   
   To remove Windows Installer information from the registry, follow these steps:
   1. Click Start, click Run, type cmd in the Open box, and then click OK.
   2. At the command prompt, locate the directory that contains the Windows Installer CleanUp Utility, and then run the following command:
      Msizap TP {7131646D-CD3C-40F4-97B9-CD9E4E6262EF}
   3. Restart the computer 
5. Disable all antivirus programs and all firewall programs that you have installed on the computer. To do this, use the System Configuration Utility (Msconfig.exe) to perform a clean start of your computer. Then disable any services that you do not need.
   
   When you use the System Configuration Utility in diagnostic mode, reenable the Windows Installer Service on the Services tab.
   
   To start the System Configuration Utility, click Start, click Run, type msconfig in the Open box, and then click OK.
6. Delete the contents of the Temp folder:
   1. Click Start, click Run, type %Temp% in the Open box, and then click OK. The contents of the Temp folder appear in Windows Explorer.
   2. In the Temp folder, click Select All on the Edit menu.
   3. On the File menu, click Delete.
      
      Note Delete as many files and folders as possible from the Temp folder.
7. Reinstall the .NET Framework 2.0. To obtain the Microsoft .NET Framework Version 2.0 Redistributable Package, visit the following Microsoft Web site: 
   Microsoft .NET Framework Version 2.0 Redistributable Package (x64)
   Note If you do not want to reinstall the .NET Framework 2.0, and the .NET Framework 1.1 or the .NET Framework 1.0 is installed on the computer, you must repair the .NET Framework 1.1 or the .NET Framework 1.0. You must repair these installations to replace the Mscoree.dll file and the URTTemp folder.