Error - trustAnchors parameter must be non-empty

I'm trying to configure my e-mail on Jenkins/Hudson, and I constantly receive the error:

java.security.InvalidAlgorithmParameterException: the trustAnchors parameter must be
    non-empty

I've seen a good amount of information online about the error, but I have not gotten any to work. I'm using Sun's JDK on Fedora Linux (not OpenJDK).

Here are a few things I've tried. I tried following the advice from this post, but copying the cacerts from Windows over to my Fedora box hosting Jenkins didn't work. I tried following this guide as I'm trying to configure Gmail as my SMTP server, but it didn't work either. I also tried to download and move those cacert files manually and move them over to my Java folder using a variation of the commands on this guide.

I am open to any suggestions as I'm currently stuck right now. I have gotten it to work from a Windows Hudson server, but I am struggling on Linux.

This bizarre message means that the trust store you specified was:

• empty,
• not found, or
• couldn't be opened, due for example to:
  • wrong/missing trustStorePassword, or
  • file access permissions.

See also @AdamPlumb's answer below.