What do I need to run the software?

The PEE Mail client is Java software. It requires a Java 8 Runtime Environment that can be downloaded for free from java.com ( more about that here...).
The PEE Mail client program uses a number of cryptographic functions provided by the JRE to encrypt and decrypt you e-mails. Unfortunately, the manufacturer of the JRE decided to restrict its cryptographic capabilities in order to comply with import restrictions of certain countries, e.g. China or maybe North-Korea. An additional download allows you to get unlimited cryptographic strengths for your JCE (if you are in a country without those restrictions). These files are called the "Unlimited Strength Jurisdiction Policy Files" and they are basically nothing else than some text files that allow Java to use cryptographic keys of any size.
The PEE client will test on start-up if those files are installed and complain if that is not the case:
Missing Policy Files Message
Missing Policy Files Message
This window closes when you hit the "OK" button and the client may or may not start. If it does, the program should work properly. But should you encounter problems, e.g. you get some weird error messages, please download and install those files. The same is necessary if the client doesn't start at all. Follow these steps to get the "Unlimited Strength Jurisdiction Policy Files":