Changing default startup directory for command prompt in Windows 7

If you added it in the control panel while your command prompt was open, that won't affect your current command prompt. You'll need to exit and re-open or simply do:

set "path=%path%;c:\program files\java\jdk1.6.0_16\bin"

By way of checking, execute:

echo %path%

from your command prompt and let us know what it is.

Otherwise, make sure there is a javac in that directory by trying:

"c:\program files\java\jdk1.6.0_16\bin\javac.exe"

from the command prompt. You can also tell which executable (if any) is being used with the command:

for %i in (javac.exe) do @echo %~$PATH:i

This is a neat trick similar to the which and/or whence commands in some UNIX-type operating systems.

As of Vista, cacls is deprecated. Here's the first couple of help lines:

C:\>cacls
NOTE: Cacls is now deprecated, please use Icacls.

Displays or modifies access control lists (ACLs) of files

You should use icacls instead. This is how you grant John full control over D:\test folder and all its subfolders:

C:\>icacls "D:\test" /grant John:(OI)(CI)F /T

According do MS documentation:

• F = Full Control
• CI = Container Inherit - This flag indicates that subordinate containers will inherit this ACE.
• OI = Object Inherit - This flag indicates that subordinate files will inherit the ACE.
• /T = Apply recursively to existing files and sub-folders. (OI and CI only apply to new files and sub-folders). Credit: comment by @AlexSpence.

For complete documentation, you may run "icacls" with no arguments or see the Microsoft documentation here and here