How to Fix an ‘Invalid Partition Table’ Error

Partition tables or partition maps store information to help load the operating system into the computer. The BIOS is a firmware that stores partition tables and the associated memory data. It’s the first thing that loads when you switch on the computer. The BIOS is required to check whether the partitions are in working condition. The most common use of the BIOS is to format your system or reinstall a better operating system (OS).

So imagine how you would feel when your OS doesn’t load, and shows a message Invalid Partition Table. Partition systems of old contained the Master Boot Record, which was responsible for the booting of the system. Since Windows Vista, manufacturers have started using a new system, GUID Partition Table (GPT), which allows the computer to be split into multiple partitions, extremely useful for dual-booting systems.

An invalid partition table error occurs due to the following reasons:

– The MBR is trying to boot from some other device than the DVD-ROM, which is the first option in the boot priority order.
– When some other device is connected to the USB port, like a flash drive or an external hard disk drive (HDD).
– There is no operating system installed on the computer.

In the following sections, we shall tell you how to fix the invalid partition table error.

On Windows XP

Step 1: Analysis

– Download Hiren’s BootCD, a free bootable software that will run at the time of booting, irrespective if your operating system works or not. Burn it to a CD/DVD and insert it in the CD drive to make it run.
– Press Ctrl+Alt+Del to restart your computer.
– Press F12 to enter BIOS and enter 1st Boot Setting : CD-ROM Group. Change the booting order to reflect the changes.
– Save the changes.
– Now restart the computer once again. Select Mini Windows XP from the options when it boots.
– After the OS gets loaded, go to Start – Programs- Administrative Tools- Disk Management to see the status of each partition, i.e. C, D, and however many drives you may have. The amount of memory allocated to each partition can be seen.
– If everything’s fine, go to Windows Explorer and check C Drive to see if an OS is installed.
– If it isn’t, restart your computer once more.
– Now run the Boot CD, and go to Master Boot Record Tools – Partition Table Doctor 3.5. This is not compatible with Windows Vista, 7, and 8.
– Click on Partition Table Doctor 3.5, and make sure all data is saved, before clicking on OK.
– You should scan bad sectors, if any, with HDD Regenerator. This software shows if any sectors have become corrupted and repairs it.

Step 2: Recover Data

– To recover data from the C drive, use recovery software like EASEUS Data Recovery or GetDataBack.
– Copy-paste the files from the D drive and save this in an external hard disk drive or flash drive.

Step 3: Fix Partition Table

– Boot the CD and choose Next to go to the next menu.
– Choose MBR (Master Boot Record).
– Next, choose Partition Table Doctor from the options.
– Click on OK.
– Now the program will open up. Click on the Operations menu and click on Rebuild Partition Table, to start repairing the damage to the partition.
– Exit the program and eject the CD.
– This would have taken care of the error. Now insert a bootable CD/DVD of your respective operating system and install it again to get your system running.

On Windows Vista, 7, and 8

– Load the Windows Vista OS (or Windows 7 & 8) bootable disc, and press any key to boot from the DVD.
– Choose the language, time, and currency. Now click on Next to continue, and click on Repair Your Computer.
– When the System Recovery dialog box pops up, choose Command Prompt.
– Type bootrec.exe and press Enter. This rebuilds the partition and fixes the problem.

These are the ways to fix the partition error on your computer. For novices and beginners not comfortable working with the BIOS, it’s recommended to get the error checked by a professional.

How to Fix Java Virtual Machine Launcher Error

Tip to fix Java virtual machine launcher error
JVM Function
The Java virtual machine is responsible for memory allocation and garbage collection, along with interpretation of byte code to machine code.
The Java runtime environment (JRE) is mandatory to be installed on your computer for certain applications to work properly. The main component of JRE is the Java virtual machine (JVM), which helps run Java applications. A java file, on compilation, produces a ‘.class’ file instead of an executable file. This class file contains Java byte code, which the JVM interprets into machine-readable instructions. JVM is platform-independent, since it provides a machine interface that does not depend on the underlying operating system and hardware architecture.

There may be times that you may get error messages while launching JVM, in situations such as booting the computer, playing games like Minecraft, or opening certain Java-based applications. Here, we have compiled a few solutions that may help you fix Java virtual machine launcher errors on Windows XP, Windows 7, and Windows 8.

Error Message #1: Could not create the Java Virtual Machine.
This error message is commonly encountered while trying to start Java-based games, such as Minecraft.
➦Open the control panel.
➦Go to system.
➦Go to advanced systems properties.
➦Click ‘environment variables’.
➦In system variables, click ‘new’.
➦Put new variable name: _JAVA_OPTIONS
➦Put new variable value: -Xmx512M
➦Click ‘ok’.

-Xmx/s is the configuration parameter that controls the amount of memory Java uses.

Xmx is the maximum heap memory size that can be allocated.
Xms is the minimum heap memory size that can be allocated.

Error Message #2: Error opening registry key.
This error may be encountered while working with Java in command prompt.
➦Go to Windows\system32 folder.
➦Delete the Java executable files, including java.exe, javaw.exe, and javaws.exe.
➦Reinstall JRE.
Error Message #3: Java Virtual Machine Launcher could not find the main class: program will now exit
➦Click ‘start’ in the main menu.
➦In the search box that appears, type ‘mrt’ and press enter. A windows utility called ‘Microsoft malicious software removal tool’ will get launched.
➦Click ‘next’ and choose ‘full scan’.
➦Reboot your computer after you’ve finished scanning.
➦Click ‘start’ and launch the system configuration utility by typing ‘msconfig’ in the search field.
➦Click the ‘startup’ tab and remove the check mark next to ‘WJView.exe’ and ‘javaw.exe’.
➦Reboot when prompted.

Error Message #4: Unable to access jarfile.
This error may be encountered while trying to open an application.
➦Click ‘start’ and go to ‘default programs’.
➦Select ‘Associate a file type or protocol with a program’.
➦Click on the extension (.jar) to view the program that opens it by default.
➦Click ‘change program’ and select the default program ‘JAVA virtual machine launcher’.
➦Click ‘close’ and check whether the issue is resolved.
➦If not, try uninstalling and reinstalling Java.
➦If the problem still persists, check with the technical support of the application which gives you the error.
If you are still not sure about all this, it would be advisable to hire the services of a qualified computer technician to sort out the problem.