Edit Jan 2018: It seems that since some time in 2017 JetBrains packs their IDEs with 64-bit Java by default and they supply the needed policy jars within jre64\lib\security\policy folder. That makes things much simpler, as there is no need to install a copy of 64-bit JDK manually in one of those folders listed below and to copy security files there.
To fix the issue now, navigate to %IDE_ROOT%\jre64\lib\security directory and copy files over from an underlying policy\unlimited folder.
Original:
While the answer chris has given is the correct one, one more clarification is in order. If you are using any JetBrains' product in 64-bit mode, then be aware, that 64-bit Java is not packed with it. You must download and install 64-bit Java DK (not JRE) yourself.
That can be the reason behind rawb's comment to chris' answer — the IDE is falling back to system-level Java. I would not recommend to follow through with rawb's advice and replace security files in your system Java. Instead, it is better to configure your IDE to run under a different copy of Java.
This article at JetBrains' support pages on selecting the version of Java the IDE will run under gives an insight in the order JDK version is looked up in. It's a little outdated as far as I can tell. If what is written there does not work for you, here's the order I figured to be working:
%YOURIDE%_JDK_64 environment variable; in case of PHPStorm it is PHPSTORM_JDK_64, for WebStorm it is WEBIDE_JDK_64, etc.
%IDE_ROOT%\jre64 directory
System Registry
- JDK_HOME environment variable
- JAVA_HOME environment variable
Now, install (or copy system-level) JDK under one of those paths and replace files as suggested.
You will have to tend to this copy of Java yourself, but, in my opinion, it will be more secure than to change system-wide JDK properties.