Certificate exception while installing another Sitecore 9 instance on same machine

Question

Installing 9.0.0 on a machine already having 9.0.1. Getting below Cert exception:

PS>TerminatingError(New-SelfSignedCertificate): "CertEnroll::CSignerCertificate::Initialize: Cannot find object or property. 0x80092004 (-2146885628 CRYPT_E_NOT_FOUND)"
>> TerminatingError(New-SelfSignedCertificate): "CertEnroll::CSignerCertificate::Initialize: Cannot find object or property. 0x80092004 (-2146885628 CRYPT_E_NOT_FOUND)"
>> TerminatingError(New-SelfSignedCertificate): "CertEnroll::CSignerCertificate::Initialize: Cannot find object or property. 0x80092004 (-2146885628 CRYPT_E_NOT_FOUND)"
Install-SitecoreConfiguration : CertEnroll::CSignerCertificate::Initialize: Cannot find object or property. 0x80092004 (-2146885628 CRYPT_E_NOT_FOUND) (edited)

Googled and found few relevant blog post like:

https://learnsitecorebasics.wordpress.com/2018/06/28/install-sitecoreconfiguration-the-certificate-does-not-have-a-property-that-references-a-private-key/

As suggested, from MMC and C Drive already removed the certificate having a prefix which I am passing in $prefix parameter. But I can not delete DO_NOT_TRUST_SitecoreFundamentalRoot and DO_NOT_TRUST_SitecoreRootCert as my previous 9.0.1 instance is using there certs.

What am I missing here?

Answer 1

Richard Dzien came to rescue on SIF Slack Channel.

If you want to keep the old SC9 install then when you install another SC9 instance make sure you set an alternative RootCertFileName parameter value in the json or the script you call it with.

If using the example script add IdentityServerCertificates_RootCertFileName = "AlternativeRootName" to the hashtable and also XConnectCertificates_RootCertFileName = "AlternativeRootName" to the hashtable if you are using the XP0 or XP1 examples. The easiest way is just to edit the createcert.json and change the defaultvalue for RootCerFileName (Line#15) though.

As a quick workaround, I changed the RootCerFileName in createcert.json file, tried reinstalling and everything went well.