Remove from PATH & generate EXE

Hi,
I'm bothered that remove a string from system environment PATH. I have to consider many cases that where the string was put in the PATH, like:
%PATH%;string
%PATH%;string;%PATH%
string;%PATH%
or just, string in the PATH

how do I remove the string from the path effectively

Secondly, is there anyway that I can generate a execution file that can execute applications and open IE with specific URL?

THANKS FOR ANY HELP

There are some functions in the Archive that allow you to add and remove directories from the PATH variable.

To execute, use Exec, ExecWait, ExecShell or the nsExec plug-in. To open web pages, use ExecShell.