Where did you install your JRE 1.3.1? Is it in the C:\Program Files\.... directory? If it was not, then you either want to remove the JRE and re-install it to the assumed default directory or you need to manually copy the 3 Javax.comm files to the JRE directory. Note that some non-US English version of Windows use a different default directory. So please search for the "java.exe" file in your drive to determine where the real java path is.
Note that when you run the SetupTL5 is run it will install those 3 files in the default directory:
C:\Program Files\JavaSoft\JRE\1.3.1\bin etc.
If you open the windows explorer and find the directory there without any other Java related files, it will mean that the JRE is not created here.
So far every user who have encountered this problem get it solved after copying the Javax.comm files to the proper directory. So please carefully review the instructions listed in the FAQ. If you still have a problem, please give us a call 1-877-689-3245 during office hour (Pacific Time) and we will try to work with you through it.
