The following guide will explain how to run java applications locally ( i.e. From a from a web developers machine ) , using the Java.policy file.

1.) If you are using both a X86 and X64 browser on your machine i would suggest changing both files .

the files are located in the following pathways

Program Files\Java\jre7\lib\security\java.policy"

and

programfiles(x86)\Java\jre7\lib\security\java.policy"

2.) Open these files and modify before the last line which is " }; " add the following

permission java.io.FilePermission "A:/-", "read";

( This will allow only the A:\ read permissions for Java )

If you wish to add more just modify the A:\ and add new lines each time .