A PC had Office 2013 Professional Plus running on its 500GB hard drive. A Nirsoft utility displayed the product key.
I changed the hard drive to 3TB, switched the BIOS from legacy to UEFI (it's a Dell Optiplex 3020), installed Windows 10, and installed Office 2013 Professional Plus, which installed, but... the product key is for a volume edition (probably MAK) and the Office 2013 image file is for retail, so it wouldn't activate. Since Microsoft's servers can recognize that Windows 10 was reinstalled on the same PC, I hoped they could recognize that Office 2013 was reinstalled on the same PC, but the mismatch between volume and retail doesn't let it get that far.
Is there a way to transfer the existing licence onto the new hard drive? I can attach the old hard drive through a USB adapter if that will help.