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How To Fix Java Virtual Machine Launcher Error

Over the years, computers have gotten relatively better at providing useful error messages. However, due to the complexity of modern software, sometimes you need a degree to even understand what you’re being told.

In this article, we’ll explain what the most common Java Virtual Machine errors mean and how you can resolve the underlying issues. Before we get to that, though, we first have to understand what a virtual machine is. Shall we begin?

What Is A Virtual Machine?

In layman’s term, a virtual machine allows your computer to simulate an entirely separate system. This makes it possible to run programs that otherwise wouldn’t be compatible with your system architecture – for instance, Android apps on a Windows PC. So what does this have to do with Java?

When a Java file is executed, it’s run through a version of the Java Virtual Machine before the code is interpreted. This means that if there’s a problem with the virtual machine, you won’t even be able to run Java programs until it’s been resolved.

“Java Virtual Machine Launcher Could Not Find The Main Class”

This sounds like a pretty serious error but in actuality, it’s one of the easiest to fix. Generally, if you’re seeing this, something has gone wrong with your Java installation. All you have to do is reinstall it. To do this:

  • Uninstall your previous Java installation. For Windows users, this is done in the Control Panel’s Programs and Features submenu.

  • Next, go to Java’s site and select the correct version for your operating system.
  • Restart your computer and try running the Java file again.

“Could Not Create The Java Virtual Machine”

Here’s another example of a vague error message that doesn’t actually help you in any way. The good news is that this error usually has one specific cause: Java is trying to use more memory than your system actually has. So how do you fix this?

  • Begin by opening the Control Panel.
  • Click System, then Advanced Systems Properties, then Environment Variables

  • Click the Add button
  • Set the New Variable Name to “_JAVA_OPTIONS” without the quotation marks.
  • Set the value to -Xmx512M” without the quotation marks. The digits before the M refer to the maximum amount of RAM allocated to Java. For instance, you could also use “-Xmx1024M” or “-Xmx256M”, if you had more or less memory to spare.

Fixes To Avoid

There are a few solutions that users on internet forums LOVE to suggest, but while they mean well, you are highly unlikely to see your problem resolved by:

  • Running an anti-malware scan (a virus that only messes with your Java Runtime Environment? For what purpose?).
  • Clearing your cache. This has nothing to do with Java, whatsoever.

  • Changing registry values. While this has the potential to resolve very specific problems, it can have catastrophic effects on your operating system and you’re more likely to break something than fix it.
  • Reinstalling your operating system. This is like amputating an arm because of a broken fingernail! Problems with a single software package can be easily resolved and won’t lead to you losing all your files, as with a fresh installation.

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Java Virtual Machine errors are rarely as serious as they appear. In fact, we’ve shown that the most common errors can be resolved in a few steps. Even though the exact options you’ll need will differ from one operating system to another, at least you now know what you have to do.

Now that you’ve read on how to fix Java Virtual Machine Launcher Error, take time to read on how to log into Kronos Timekeeper from home.

Justin Stuart

Justin is the head writer for My Tech Reviewer and he ensures that readers always get what they are looking for. He's a hard worker and spends more hours writing for My Tech Reviewer than he works at his part-time electrician job.