Create a cert to upload to Entra Enterprise App.

new_cert.ps1

# -----------------------------
# VARIABLES
# -----------------------------
$myName        = "myAppCert48"
$certName      = "CN=$myName"
$certValidity  = 48    # months
$certPath      = "Cert:\CurrentUser\My"
$pfxOutput     = "C:\temp\$myName.pfx"
$cerOutput     = "C:\temp\$myName.cer"
$pfxPassword   = Read-Host "Enter PFX password" -AsSecureString

# -----------------------------
# CREATE SELF-SIGNED CERT
# -----------------------------
$cert = New-SelfSignedCertificate `
    -Subject $certName `
    -CertStoreLocation $certPath `
    -KeyExportPolicy Exportable `
    -KeySpec Signature `
    -KeyLength 2048 `
    -Provider "Microsoft Enhanced RSA and AES Cryptographic Provider" `
    -NotAfter (Get-Date).AddMonths($certValidity)

Write-Host "Certificate created with Thumbprint: $($cert.Thumbprint)"

# -----------------------------
# EXPORT PFX (private key)
# -----------------------------
Export-PfxCertificate `
    -Cert $cert `
    -FilePath $pfxOutput `
    -Password $pfxPassword

# -----------------------------
# EXPORT CER (public key)
# -----------------------------
Export-Certificate `
    -Cert $cert `
    -FilePath $cerOutput

Write-Host "Export complete:"
Write-Host "  PFX: $pfxOutput"
Write-Host "  CER: $cerOutput"