The different certificates can be found in the following keystore :
%JAVA_HOME%/jre/lib/security/cacerts
If you want to list the trusted certificates :
keytool -list -keystore %JAVA_HOME%/jre/lib/security/cacerts
The password is optional to list.
If you want to add an entry :
First, export the certificate to import, let’s say it will be c:\cert.crt. The best way to do it is using firefox, right-click on the lock picture in the URL, and after a few clicks, you have an export feature.
Then type :
keytool -import -alias my-cert -file c:\cert.crt -keystore %JAVA_HOME%/jre/lib/security/cacerts
The default password is: changeit
The alias is a user-defined label, choose it wisely, to remember if you need it one day, what it was.
With all this, you should be able to trust the certificate and have everything working again.