Thanks to Paul Kiddie. Windows 7 expects a license server on the local network which isn’t present when you install Windows 7 Enterprise on a home machine. As a result you can’t activate Windows (fails with error 0×8007232B). You need to install the key using:
slmgr -ipk xxxxx-xxxxx-xxxxx-xxxxx-xxxxx (put your key here)
After this is successful you can activate windows like normal.