I downloaded an ISO of Windows 7 Home Premium from the Windows website and made a clean install on my Lenovo IdeaPad Y580.
Before re-installing I made a screenshot of my product key , which was shown by a key finder. During the re-install process I typed my product key. Installation was successful.
However I realized there might be a problem: Start -> My Comp -> properties -> Windows Activation, there was a message: "15 days to activate. Activate Windows now". I tried to activate this, but I got a message: "The Windows 7 Home Premium product key you typed is invalid for activation".
I checked the product key, and encountered another problem: the product key shown by Everest and the key on the underside of the laptop do not match.
I tried both keys but both failed to work.
What else can I do?
There are two ways you can try:
1) Re-enter the product key again later
2) phone activation
Below here are useful information for your reference:
You do not have to purchase any special Windows 7 media once you have a valid Windows 7 Home Premium key on the back of your laptop. You can download a copy of Windows 7 and use your key, as you are attempting to do.
You may use any disc (OEM, retail, upgrade, VL) with Windows 7. It is not "media-specific." You may also download a legitimate copy of Windows 7 from Microsoft, burn it to a DVD and use it with an OEM COE key. During the installation process, the software will customize itself to the version that corresponds to the key.
Windows 7 media is different from Windows XP media. For example, you may have retail and O.E.M. Windows XP discs. When doing a fresh installation on a machine which has an XP COA key on the back, you have to use the O.E.M. XP installation disc. When you wish to use a retail Windows XP key you had purchased, you must use a retail XP installation disc.
This is not true for Windows 7. You can use a retail version or OEM version to do a fresh installation using the WIndows 7 COA Key located on the back of the machine.
Check if you wish to install the 32-bit or 64-bit version of Windows 7 Home Premium. If you have at least 3GB of memory, you should go for the 64-bit version.
Double-check that you downloaded from an official Microsoft location, and that it's the 32-bit or 64-bit version of Windows 7 Home Premium and not Windows 7 Pro or some other version you downloaded by accident. If you still have difficulty, then your key may have been activated before, used on another laptop or some other issue exists.