Internet Explorer 7 B1 Installation

Hello,

I am trying to install IE7 Beta 1 on Win XP Sp2.

When I go through the wizard, I get the error:
Setup was not able to automatically validate your copy of Windows.

Then it opens Microsoft's website and I get the Validation Error:
[0x80080299] Validation Incomplete: Unable to Perform Validation
You have encountered an unknown error. Please contact your local product
support team for further assistance with this issue.

My Windows is actually valid because if I go through Windows validation
myself, I get thank you for using genuine windows straight away.

I also tried on my Genuine Windows laptop and got the same problem.

Can anyone help me install IE7?

Thanks for your help.