[www-jigsaw] <none>

I have created a utility where the applet reads from a file and displays an out put.
Though the utility runs ok on a file system on a hard disk, if i write the same 
application on an CD the utility gives an error 
---
com.ms.security.SecurityExceptionEx[app1.action]: cannot access file /E:/index.txt
        at com/ms/security/permissions/FileIOPermission.check
        at com/ms/security/PolicyEngine.deepCheck
        at com/ms/security/PolicyEngine.checkPermission
        at com/ms/security/StandardSecurityManager.chk
        at com/ms/security/StandardSecurityManager.checkRead
        at java/io/FileInputStream.<init>
        at java/io/FileReader.<init>
        at app1.action
        at java/awt/Component.handleEvent
        at java/awt/Component.postEvent
        at java/awt/Component.postEvent
        at java/awt/Component.dispatchEventImpl
        at java/awt/Component.dispatchEvent
        at java/awt/EventDispatchThread.run
---

These lines are used to access the file 
String file = getCodeBase().getFile();
BufferedReader b1 = new BufferedReader(new FileReader(file+getParameter("FileNm")));