I need to know how to fix Java Error 1603.

I’m assuming removing Java from your machine and rebooting just one last time is not on your list.

I think it is a server error, not a PC level error.

The Java Error 1603 means that there was a fatal error during installation while running the Windows installer.

That does not tell me much other than the fact that it is the Java equivalent of the blue screen of death.

The error means that the installer did not get the resources it needed to install, or it encountered something it did not expect.

I did not expect this error. So how do I fix it?

One possibility is that an installation file it needs is missing, like the data1.cab file.

That cab file went away after Java 7.

You could try deleting the installer and all its associated files and downloading the installer again, in case the installer itself downloaded without everything you need.

That’s as bad as the updating of the updater for Java.

The updater itself does not update, it is only Java updating constantly. However, you can get the error if the prior version of Java has remnants haunting the current install.

Of course Java will haunt me the rest of my days. I’ll be so glad when they get rid of it with HTML5.

That does shift a lot of web-based apps to JavaScript, but it does not eliminate Java being used for interactive functions on a website or installed apps. Do search the system for prior versions of Java on the machine and remove them before trying again.

And reboot the machine, just to make sure it clears out the fragments. But what if removing old versions and installing the installer again are not enough?

It is possible that the Java update did not complete, so it cannot install because it thinks it is installed or at least partially installed on the machine.

How the heck do I clean that up?

It could have updated the registry key before dying, so you need to clean up the registry entries for the version that failed to update and maybe the old versions as well.

I would rather not touch registry keys.

So make sure that you are not using an app that uses Java when you run the installer. That could be as simple as having a browser open running Java applets while you run the installer.

Closing all browsers, rebooting, and resisting the temptation to Google the installation status messages is certainly something I can try.

The last gaps is making sure AVG antivirus did not scan the file and prevent it from downloading all the installation files.

Makes sense, since it considers Minecraft’s installer to be a virus.

Not really, given how many parents consider Minecraft a plague on their pre-teens.

Please take the opportunity to connect and share this video with your friends and family if you find it useful.