Here you go , i used Dell 2.1 SLIC + Certificate Included:-
1. Copy and paste ******.XRM-MS certificate file into C-Drive.
2. After pasting this file into C-Drive, go to START - ALL PROGRAMS - ACCESSORIES - COMMAND PROMPT. Right click on Command Prompt and RUN AS ADMINISTRATOR.
3. When Command Prompt opens, type at the prompt: slmgr.vbs -ilc c:\********.xrm-ms and hit the Enter Button. Wait for the Script Host to answer you with a message that the license was installed successfully....this could take a few minutes and so be patient.
4. After receiving the message that the license was installed successfully, type at the command prompt:
slmgr.vbs -ipk *****-*****-*****-*****-***** (Replace with any OEM SLP Product Key for your installed version of Windows 7 , they are not hard to find).Be Patient and wait for the message to say that the Product Key was successfully installed. After it says successfully installed, reboot the computer.
5. When you are back at your desktop, go to START - COMPUTER - right click on Computer and choose PROPERTIES and see if it is activated with an OEM product ID.http://dl.dropbox.com/u/747181/Dell%20Dimension%20E520%20v2.4.0%20Dell%202.1%20SLIC%20By%201234s282.zip
Flash at your own risk!
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