Precision T1500: Installing Office 2007 Pro onto clean Windows 10 install

You cannot use the Vista key to upgrade to Windows 10 from what I know.  You can only use Windows 7 and higher.  The Windows Vista key won't work on Windows 7 either.  One thing to look at is what version of Windows are you installing?  Not meaning Pro or Home, but OEM or Retail?  Technet keys etc., probably will only work with OEM channel builds.  I've noticed in my experience that OEM keys will not work with Retail channel versions of Windows.  

Sorry.  The 2nd paragraph of my original post should read:

I have upgraded the RAM to 16Gb and replaced the hard drives with a SSD and bigger SATA data drive, and have installed Windows 10 Pro onto the SSD.  However when I have come to install Office 2007 Professional onto the drive the key is not accepted.  The message (in Red) reads: "The key is incorrect.  Verify that you have the correct key and then retype it.".

The customer has bought a full license for Windows 10 Pro and I've installed that onto a new SSD drive.  My problem is the Office 2007 install which will not accept the key, even though I know that this is the correct key used on the previous Windows installation on this machine!

I setup this machine some six years ago  for a customer and at the time it had Vista Business and Office Professional 2007 pre-installed.  They have decided it is time to upgrade the machine including moving to Windows 10. I have upgraded the RAM to 16Gb and replaced the hard drives with a SSD and bigger SATA data drive, and have installed Windows 10 Pro onto the SSD.  However when I have come to install Windows 7 Professional onto the drive the key is not accepted.  The message (in Red) reads: "The key is incorrect.  Verify that you have the correct key and then retype it.". I know I have the correct key - I have a number of key finder programs (including AIDA64) which have never let me down in the past.  I am using an ISO file from a standard Microsoft CD image which I have from my time as a TechNet member which I know works.

Where did you get this Windows 7 Pro key?

There was no FREE upgrade from Vista to WIndows 7 that I know of.

In addition, the T1500 has not been tested by Dell for Windows 10.

Dell did offer free upgrades to windows 7 from vista when windows 7 was just coming out.  It came on a disc with its own COA key.

I am re-reading his post, and I am confused.

He writes "have installed Windows 10 Pro onto the SSD"

Yet he then writes that the Windows 7 Pro key does not work.

He writes of using a key finder program. Why would that be needed if he has a Windows 7 Pro COA from Dell?

It looks like he is trying to use this Windows 7 Pro key of unknown origin to activate the Windows 10 Pro.

Yeah I had to read it several times myself ;-)

Is the Office 2007 key accepted here?

http://dellwindowsreinstallationguide.com/download-office-365/

Edit wrong link:

https://www7.downloadoffice2010.microsoft.com/o12/registerkey.aspx?culture=en-GB&ref=o12&country_id=GB