Windows Software Licensing Management Tool, slmgr.vbs is a command line licensing tool. It is a visual basic script used to configure licensing in Windows and also helps you see the licensing status of your Windows 7 or Windows 8 installation.
To see the licensing status of your Windows 7 installation type slmgr.vbs /dlv and hit Enter. The following dialog box will appear.
To get all the Activation IDs for the installed version of Windows, type slmgr.vbs /dlv all in start search and hit Enter.
Because of WMI changes in Windows 7 and Windows Server 2008 R2, the Slmgr.vbs script is not intended to work across platforms. Using Slmgr.vbs to manage a Windows 8, Windows 7 or Windows Server 2008 R2 system from the Windows Vista operating system is not supported.
If you are looking for more Slmgr.vbs Options visit TechNet.
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