Redirecting main parent window with JavaScript

[Paul Ingles]

I'm trying to get some JavaScript so that a number of pop-ups can figure out the parent that spawned them all, close themselves and re-direct the main parent. It works as I want (if it's coming from a pop-up then it'll spawn a new window), but, if I click to show the first pop-up, then close the main parent window, and continue through to the page that executes the below code, it throws up an error:

function findWindow()
{
var currentWnd;
currentWnd = self;

while (currentWnd.opener != null  && !currentWnd.opener.closed)
{
	var oldWnd = currentWnd;
	currentWnd = currentWnd.opener;
	oldWnd.close();
	
}

if (!WindowIsPopup(currentWnd))
{
	currentWnd.document.location.href='http://www.microsoft.com';
} else {
	// It's a pop-up, so close it and open a new page altogether.
	open('http://www.theregister.co.uk');
	currentWnd.close();
}

}

Basically, I want to be able to do a check to find out whether I've reached the main parent window, and if it's not open, spawn a new one etc. If anyone has any suggestions, or has done this kind of thing before I'd appreciate their thoughts. Thanks, -- Paul "Put the key of despair into the lock of apathy. Turn the knob of mediocrity slowly and open the gates of despondency - welcome to a day in the average office." - David Brent, from "The Office" MS Messenger: paul@oobaloo.co.uk Download my PGP public key