In the case that your applet is configured to use more than 1536M maximum memory, you will need to use 64-bit java to launch the applet (Ex: Data Mapper, Process Designer)
If you are attempting to launch an applet using 32 bit java, the splash screen will appear and disappear but the applet will not load.
A) If you only have 64-bit java installed, windows will automatically launch the applet using 64-bit java.
B) In case you have 64-bit java and 32-bit java installed, you will need to make a registry edit to allow the 64-bit java to be used as default when launching the applets. Use the following steps:
1) With administrative permissions, click Start > In the search box type "Run"
2) In the Open field type "regedit"
3) Navigate to the path \HKEY_CLASSES_ROOT\JNLPFile\Shell\Open\Command
4) Right-Click on the (Default) Name > Modify
5) In the Value data field, enter the path to the 64 bit javaws.exe. For example ("C:\Program Files\Java\jre7\bin\javaws.exe" "%1")
6) Click Ok > then press F5 to refresh and confirm the change has been made
Launch the mapping applet, which will now be using the 64 bit javaws.exe