We have exchange 2007 server on which a self signed certificate was installed.
AS self signed cerificate validity is only for one year the self signed certificate has expired now as one year has passed.
How can i generate a new self signed certificate for my exchange server.
Yes that is true
Actually you want to install certificate services and create a root certificate that has a lifetime of minimum 5 year to 20 years (your choice) and install that certificate on your clients
Create a certificate for your exchange server requesting the certificate from your internal certification authority and install it into your exchange server (default 2 years valid)
Renewing the certificate does not need any change on clients as they have the root certificate that is valid for 5 to 20 years
You can follow the procedure here: