Ehlo

The full exception is:

org.springframework.beans.TypeMismatchException: Failed to convert property value of type [javax.mail.Session] to required type [javax.mail.Session] for property 'session'; nested exception is java.lang.IllegalArgumentException: Cannot convert value of type [javax.mail.Session] to required type [javax.mail.Session] for property 'session': no matching editors or conversion strategy found
Caused by:
java.lang.IllegalArgumentException: Cannot convert value of type [javax.mail.Session] to required type [javax.mail.Session] for property 'session': no matching editors or conversion strategy found

In my case when I got this exception, what I did is moved the activation.jar and mail.jar file from the web app lib directory to CATALINA_HOME/common/lib.

And it worked just fine.