Hello,

I have seen the EULA discussed widely in regard to the terms about use in
Virtualization:

"MICROSOFT WINDOWS VISTA ULTIMATE

ADDITIONAL LICENSE TERMS

...

6.    USE WITH VIRTUALIZATION TECHNOLOGIES.  You may use the software installed
on the licensed device within a virtual (or otherwise emulated) hardware
system on the licensed device."

It seems to me that this is reasonably going to create confusion in those
reading the EULA, as it really is open to interpretation.  One interpretation
is that it does imply you can use Vista Ultimate within VPC and it doesn't
say anything about another licence.  The second interpretation is that it
does not provide any additional rights to use it within a VPC (i.e. as a
guest) on top of using it as a host, it merely states that you can use the
licence you have within a VPC.

I am not trying to pull a fast one on MS, but I really did genuinely read it
as the former.  It seems reasonable too, given that there is quite a price
premium paid for Ultimate (sure, there are other extras too I admit).  What
reinforced my belief in my interpretation was that clause 6 is listed under
"Additional Terms" so you might quite easily think that when it's saying "you
may use xxxx" it is allowing you something extra that is not allowed for the
lower editions of the OS (I may not have explained this last point too
eloquently).

I only want to do this as I wish to do some basic development without
messing up my home PC's configuration and stability.  Is Microsoft really
keen to disallow me from doing this?

My question is: why didn't MS spell this out more clearly in the EULA?  
Being explicit about what is and isn't allowed would not be difficult and
could probably be done in very few extra words.

Cheers,
Neil