If you run this:
and you get this:
it simply means that you are using a 32bit JVM instead of a 64bit JVM.
check "java -d64"
java -d64 -version Error: This Java instance does not support a 64-bit JVM. Please install the desired version.
java -Xms4096m Bla
and you get this:
Invalid initial heap size: -Xms4096m
The specified size exceeds the maximum representable size
it simply means that you are using a 32bit JVM instead of a 64bit JVM.
check "java -d64"
java -d64 -version Error: This Java instance does not support a 64-bit JVM. Please install the desired version.