Originally Posted by Java Troubleshooting

If you see the following error message
This program cannot be run in DOS mode.

then do the following:
Open the MS-DOS shell (Windows/Start/Programs/MS-DOS Prompt)

Right-click on the title bar

Select Properties
Choose the Program tab
Push the Advanced button
Make sure the item "Prevent MS-DOS-based programs from detecting Windows" is unchecked
Select OK
Select OK again
Exit the MS-DOS shell
Restart your computer.