Good place to read up on SLIC activation is My Digital Life forum.
As you didn't extract the *.xrm.ms file from original installation you may find the correct version on their site. Can then use insert commands to inject said file and associated product key, e.g.
Manually install a certificate
1. First, be sure to have SLIC 2.1 in your BIOS (you can use the SLIC DUMP ToolKit to check its presence).
2. Download certificates.
3. Put in C:\ the certificate that belong to your SLIC's brand.
4. Type cmd in Start menu.
5. Right-click on the first result (cmd.exe) and click on Run as administrator (confirm by clicking Yes if required).
6. Type (Important: Replace "NAME" with the name of your certificate)
slmgr -ilc C:\NAME.xrm-ms
7. Press ENTER and wait until a message confirms that the certificate has been correctly installed.
Manually install a key
1. Type cmd in Start menu.
2. Right-click on the first result (cmd.exe) and click on Run as administrator (confirm by clicking Yes if required).
3. Type (Important: Replace the XXXXX with a valid OEM SLP product key)
slmgr -ipk XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
4. Press ENTER and wait until a message confirms that the key has been correctly installed.