If you’re trying to install Powershell 2.0 CTP3 on a Windows PC with Powershell 1.0 already installed, the installation wizard will stop with the following warning.
Before the wizard will continue, you have to uninstall Powershell 1.0.
Open Control Panel. Select Show updates and browse to Windows XP – Software Updates. Click on Remove to uninstall Powershell 1.0.
If you don’t have an entry in the Add/Remove Programs control panel, You can find the Powershell 1.0 Uninstaller here:
- C:\WINDOWS\$NtUninstallKB926139-v2$\spuninst\spuninst.exe
- C:\WINDOWS\$NtUninstallKB926139$\spuninst\spuninst.exe
After uninstalling Powershell 1.0 you’re able to install Powershell 2.0 CTP3.
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How to uninstall Windows PowerShell 1.0
To uninstall Windows PowerShell 1.0, follow the steps that are appropriate to your operating system.
Windows Vista
Click Start, type appwiz.cpl in the Start Search box, and then press ENTER.
In the list of tasks, click View Installed Updates.
In the Uninstall an update list, right-click Windows PowerShell(TM) 1.0 (KB928439), and then click Uninstall.
Follow the instructions to uninstall Windows PowerShell 1.0.
Note If you disable Windows PowerShell by using the Turn Windows Features on or off option, this does not satisfy the Compatibility Check process. You must uninstall Windows PowerShell.
Windows Server 2003
Click Start, click Run, type appwiz.cpl, and then click OK.
Click to select the Show updates check box.
In the Currently installed programs and updates list, find the entry for the hotfix that installed Windows PowerShell 1.0. Depending on the installation package that was used, this entry resembles one of the following:
Hotfix for Windows Server 2003 (KB926139)
Hotfix for Windows Server 2003 (KB926140)
Hotfix for Windows Server 2003 (KB926141)
Click the Windows PowerShell hotfix entry, and then click Remove.
Follow the instructions to uninstall the hotfix for Windows PowerShell 1.0.
Note By default, if Windows Server 2003 Service Pack 2 is installed on the system, PowerShell 1.0 cannot be uninstalled. To resolve this issue, follow these steps:
Follow the steps in the following Microsoft Knowledge Base (KB) article, 931941, to trust Windows PowerShell 1.0 that was introduced in KB926139:
931941 (http://support.microsoft.com/kb/931941/ ) The Oobmig.exe tool is available to restore trust to out-of-band updates after you install Windows Server 2003 Service Pack 2
Note You may have to restart the computer.
Check whether the update can be uninstalled by using Control Panel. If the update cannot be uninstalled in this manner, uninstall PowerShell manually from the following location:
C:\WINNT\$NtUninstallKB926139$\spuninst\spuninst.exe
Note You may have to restart the computer.
Windows XP
Click Start, click Run, type appwiz.cpl, and then click OK.
Click to select the Show updates check box.
In the Currently installed programs and updates list, click Windows PowerShell(TM) 1.0, and then click Remove.
Follow the instructions to uninstall Windows PowerShell 1.0.