Phone your regional MS activation centre. Google may be able to help you.
You can download an appropriate iso on another PC with a faster connection, or use the MCT to create a bootable device which you can use for either a clean install or an upgrade.
I think to know how to assist you better is to know HOW you installed Win 10.
Did you upgrade from your running Windows 7 OR did you boot from the USB and do a fresh/clean install??
Great idea to ring Microsoft as by far the easiest and quickest as it was all way above my head so many thanks as I'd never heard of this useful option before. Spent about an hour on the phone just now letting the guy take over the pc remotely, eventually saying that it's a bit more complicated than he can manage so someone higher up will be calling on Friday to sort it out properly and install Win 10. Turned out that it's still basically Win 7 and not Ultimate so it seems that Ultimate could have been messing up things.
Thanks again everyone
If you try to install Windows 10 on a rather old PC, you may have to disable some devices so Windows won't try to find drivers for them and slow or even block the upgrade. I would go to Device Manager and disable any device non essential for the upgrade, that is audio, LAN or Wi-Fi (assuming you have downloaded the ISO you shouldn't need an Internet Connection until the upgrade is completed), cameras, etc. Disable anything you think might interfere with the Upgrade process like antivirus, startup applications etc. After a successful upgrade from 7 to 10 you can then enable (one at a time) your devices and install drivers if necessary. Even if Windows 10 automatically find drivers, you may have better performance and enable more features if you install Official (OEM) drivers. After all drivers have been installed successfully, you can then enable your disabled startup applications and antivirus. For more details see this thread: Let's run Win10 on really really old hardware
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