How do I determine which Windows 7 installation disk I used to update

[Joeacusa]

I have 3 computers, each with Windows 7 installed, using legally purchased disks. I wish to remove Windows 10 from a Dell Inspiron 15 laptop and re-install the Windows 7, but I don't know which disk to use. How do I determine which disk, and it required ID number, to use? Or does it make a difference?

Joeacusa

 

[SIW2]

Have you got the license key for the original win 7 installation on the Dell inspiron? It is probably on sticker somewhere on the machine.

 

[Joeacusa]

The Dell originally had Windows 8 on it and I installed Windows 7 from a disk that I have, but I don't know WHICH disk, or, therefore, which of the 3 activation codes on the 3 disks.

 

[DavidE]

The installation disc (DVD) does not have a key built into it.
The key should be on a COA sticker that was supplied with the purchased disc.

If you still have 2 running PC's with Win 7 that you purchased and installed, you can use a tool such as Belarc Advisor to see key on that PC.
That should leave you with only one "unknown" key that was used on the Dell laptop, now running Win 10.

Belarc Advisor - Free Personal PC Audit, for software, hardware and security configuration information on your computer. Software license management, IT asset management, cyber security audits, and more.

 

[Joeacusa]

Thanks. I'll try that.