Hello R0ger_r4bbit,
Yes, there is a rule against installing a consumer license for Windows more that once on any one computer, or on more than one computer, at a time.
You have earned a NoGo at the Microsoft Software Licensing station. Additional training on this Mission-Essential task can be had by clicking Start>Run, then type
winver and click OK. In the resultant dialog box, click the link for Microsoft Software Licensing Terms.
You may retest after uninstalling Windows 7 from your desktop. Or, you can earn a Go by purchasing a second license for W7 at the PX or directly from Microsoft by clicking on the Resolve Now links that are being displayed in the nongenuine notices
you are seeing on your computer.
Carry on.
Buy Office 2007 Now, Get Office 2010 Free http://office2010.microsoft.com/en-us/tech-guarantee/microsoft-office-2010-technology-guarantee-FX101825695.aspx?CTT=97