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After installing Oracle 11g client, when I tried to run SQL Developer it's asked me to give it java.exe path. As I didn't know I gave it the wrong path to program files java installation.
Which I later found out that I should have given the path to java.exe inside oracle folder.
Now every time I run it doesn't ask me for java.exe path, but shows the next error: Unable to find Java Virtual Machine.
I think to correct this I need to give Java path to it in oracle folder, but how to change the path that I have already given?
I faced a similar issue and i fixed it by following steps:
step1: Go to where your SQL Developer is installed.
step2: Go into the sqldeveloper folder (inside SQL developer installation folder) >bin
step3: just edit the sqldeveloper.conf .
You will see line called “SetJavaHome”, that’s where we need to fix.
Remove that line, then try starting the SQL Developer again:
use this link for further references.
来源：https://stackoverflow.com/questions/24008395/sql-developer-error-unable-to-find-java-virtual-machine