com.google.gerrit.server.mail.OutgoingEmailValidator not found

[Jungho Ahn]

Hello,

I'm trying to change project config through web ui: projects/general/edit config, but I got 500 internal error.

When I checked the log, 

ERROR com.google.gerrit.httpd.restapi.RestApiServlet : Error in POST /changes/

com.google.gerrit.server.git.UpdateException: com.google.gerrit.server.project.InvalidChangeOperationException: invalid author

...

I'm not sure what 'invalid author' means. I'm in 'Administrator' group.

And I tried to registered my account's email, but it failed too:

java.lang.NoClassDefFoundError: Could not initialize class com.google.gerrit.server.mail.OutgoingEmailValidator

        at com.google.gerrit.server.mail.OutgoingEmail.add(OutgoingEmail.java:384)

        at com.google.gerrit.server.mail.RegisterNewEmailSender.init(RegisterNewEmailSender.java:49)

...

Should I install any external lib or plugin?

Thanks,