It is frustrating when you are trying to get something done and you get an error message that you least expected. Don’t worry, we know how to fix it. One of the main reasons for this is incorrect version of JRE on your system is that you are using an incompatible version of JRE. If you are using a 32-bit system, make sure you have 32-bit version of JRE installed. Similarly, on a 64-bit system, you must have 64-bit JRE. If you mix it, then FrameMaker will fail to recognize it.
This issue and its resolution has been discussed in more details in this thread.