How to move Windows 8.1 OEM to a SSD?
How to move Windows 8.1 OEM to a SSD?
You're facing a common issue when upgrading hardware. Since you don't have the serial key, moving Windows 8 to an SSD without reactivation isn't straightforward. You'd likely need to use a recovery tool or reinstall the OS from a bootable USB drive. Consult the PreBuilt documentation or contact their support for guidance on transferring Windows 8 to a new SSD.
If possible, try to reinstall Windows completely. It will work much better without the chance of harming or losing any data. Be sure to install on the SSD during the process.