Java: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

Question

I have a class that will download a file from a https server. When I run it, it returns a lot of errors. It seems that I have a problem with my certificate

Answer 1

In my case I'm running MacOs High Sierra with Java 1.6. The cacert file is in a different location than referenced above in Gabe Martin-Dempesy's answer. The cacert file was also already linked to another location (/Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Home/lib/security/cacerts).

Using FireFox, I exported the certificate from the web site in question to a local file called "exportedCertFile.crt". From there, I used keytool to move the certificate into the cacert file. This fixed the problem.

bash-3.2# cd /Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home/lib/security/
bash-3.2# keytool -importcert -file ~/exportedCertFile.crt -alias example -keystore cacerts -storepass changeit