JoeBobUSA22 said in
If you use the old hard drive in the old computer then, no, you shouldn't need to re-activate. However, if you move the old drive to a different computer then you will probably have to activate since way too much of the "old" system has changed (because of the motherboard, NIC, CPU, and everything else in your "new" computer environment in which you slid the drive). If the activation fails, a telephone number during the failed activate process should give you a contact to Microsoft. Call them to activate manually but be prepared to explain and prove the legal transfer of the software. They will need the product key. If it is an OEM version, say goodbye to Microsoft since you are using an illegal version that you moved from the computer to with the OEM license was tied.