"JDK 5.0 or newer cannot be found on your machine"

When trying to start Delta2D I get this error message and nothing happens.

Usually there is no necessity for an extra java installation for using Delta2D. The phenomenon you experience is very likely a mixup of 32-bit and 64-bit Versions of Delta2D, as if there was an installation of 32-bit Delta2D which was upgraded with a 64-bit update, or vice versa.

To resolve this we recommend a complete new installation of Delta2D:

• Locate all previous installations of Delta2D which could be mixed up with your working installation. Please look at:
  C:\Program Files\DECODON\Delta2D  (for 64-bit installation on Vista64 or 32-bit installation on Vista32) and
  C:\Program Files (X86)\DECODON\Delta2D  (for 32-bit installation on Vista 64-bit)
• Make a backup of the folders for having the license file and in case there are customized settings you might want to reproduce easily
• Remove or rename the original folders Delta2D (This is, by the way, the crucial part of the manual method of uninstalling Delta2D manually, when the automatic uninstall fails. Additionally you might want to remove the entries from the start menu and the desktop)
• Download a copy of Delta2D from your Private Download Area and make sure you take the one you need (32/64-bit), whereas we always recommend the 64-bit version for 64-bit systems.
• Install Delta2D, and, on being requested for the license, take the file license.lfk from your previous installation.