Before You Ask
Why do I sometimes get kicked on 1.12.2 servers?
This happens because of a bug in the Netty library, which Minecraft depends on. Pressing the "Reconnect" button usually fixes the issue within seconds. Alternatively you can use ForgeWurst, which is not affected by this bug.
How do I install Wurst?
Please read our installation tutorial.
I have Minecraft 1.12.2. Why does the Wurst MC 1.12 installer say that it couldn't find my Minecraft installation?
You need Minecraft 1.12, not 1.12.2. Just download 1.12 through the Minecraft launcher and you'll be fine.
Why can't I run the cross-platform Wurst installer? (.JAR)
Maybe you don't have Java installed (or you have an outdated version*). Maybe you have configured your computer to open .JAR files with some other program than Java. Or maybe you are simply using "java.exe" instead of "javaw.exe".
*There are known problems with Java 9 that might prevent the installer from working. Despite it being newer, Oracle has officially declared Java 9 to be "end of life" and "end of support" as of March 2018, meaning that this issue will not be fixed. We recommend using Java 8 instead.