When having an issue with Windows activation see, if the following solution will help you. Going through the normal Windows activation cycle in Windows 7 (System -> Activate Windows) may not work, as it did for me and when trying to install Windows 10 there was no option because it said Windows had not been properly activated.
Here is how I solved the Windows 7 not activating issue
1. Run Command Prompt as Administrator
Type cmd in the search box in Windows 7 start menu. Then once the Command Prompt (cmd.exe) appears, right click it and select “Run as administrator)
2. Run the command slmgr.vbs -ato
The command will force Windows activation with the vba script. It will take some time and you will get a confirmation in a small window that your Windows activation has been successful.
Make sure you’re in the system32 folder with the command prompt when running the script. If not, then using the cd command move to system32 folder before executing the slmgr.vbs -ato command. (C:\Windows\System32).
3. Restart the computer