You should also report them to MS so other people don't do the same.
https://www.microsoft.com/en-us/piracy/reporting/faq.aspx
https://www.microsoft.com/en-us/piracy/reporting/faq.aspx
It was 8.1 Pro, 64bit.
Is OcUK license for single PC?
Not always true, I bought 2 copies of Windows 8 Pro for £15 each direct from Microsoft, I only received an email.Legit resellers. If you get a key via email then it's never legit.