I have a self signed certificate that was generated on a Windows 10 machine using the Powershell command:
New-SelfSignedCertificate -DnsName ServerNameHere -NotAfter (Get-Date).AddYears(20) -FriendlyName "Test API Cert" -CertStoreLocation cert:\LocalMachine\My
I exported this certificate with a private key to a PFX file and transferred this to my old Windows 7 test machine. (I have a legacy customer I am working with who still has some Win7 devices that I need my software to work on)
On the Windows 7 machine I imported the certificate into the Personal store.
I then opened the MMC, added the certificate add in and opened the personal store. It doesnt show the certificate.
Is there some reason that it is not showing here?
The problem is that you accidentally installed the certificate to Current User store. When you double-click on PFX certificate, Certificate Import Wizard defaults to Current User\Personal store. It doesn't offer Local Machine store on Windows 7/Windows Server 2008 R2 or older OS versions. Store location selection choice was added in Windows 8/Windows Server 2012 and newer.
This is why you can't install PFX to local machine store from Windows Explorer on Windows 7. On these operating systems, you have to explicitly open Certificates MMC snap-in focused on local machine context and import certificate from there.