How to renew self-signed certificate on Exchange 2k7 server
To renew a self-signed certificate, use this pshell command:
Get-ExchangeCertificate -Thumbprint 67455EECD51C972C2DFDAE56CF927B8851C73048 | New-ExchangeCertificate
To remove the old certificate use this command
Remove-ExchangeCertificate with the thumbprint value of the old certificate for eg:
Remove-ExchangeCertificate -Thumbprint E3ED4FE364679696969AF93148A024669AE4CF4E