Can not get rid of xml loaded image scroller when navigate out of the page.

I still have the same error:

ArgumentError: Error #2025: The supplied DisplayObject must be a child of the caller.

    at flash.display::DisplayObjectContainer/removeChild()

    at acolyte51c_AppsPopUpsThumbs_fla::mainsite_mc_2/removeScrollerF2()[acolyte51c_AppsPopUpsThumbs_fla.mainsite_mc_2::frame73:404]

    at flash.display::MovieClip/gotoAndPlay()

    at acolyte51c_AppsPopUpsThumbs_fla::mainsite_mc_2/gotoFrame2()[acolyte51c_AppsPopUpsThumbs_fla.mainsite_mc_2::frame73:372]

Line refers to this:
scroller.parent.removeChild(scroller);

I tried adding .parent one at a time and retest but it did not work either. I added up to five instances (scroller.parent.parent.parent.parent.parent.removeChild(scroller);

I implemented your code like this:

var scroller:Object = MovieClip(root).getChildByName("thisOne");

I get no more errors, but the scroller is still stays on the screen.

Maybe it helps - here is the code section where I construct the scroller:

//thumb scroller////////////////////////////////////////////////////////////////////////

//load xml

var xmlLoader:URLLoader = new URLLoader();

/////Parse XML

var xmlData:XML = new XML();

var xmlPath:String = "loadingAssets/appThumbnails/slideshow_image_scroller_ActiveTuts_mine/app_thmbs_imgs60x90.xml";

xmlLoader.load(new URLRequest(xmlPath));

xmlLoader.addEventListener(Event.COMPLETE, LoadXML);

function LoadXML(e:Event):void {

    xmlData = new XML(e.target.data);

    buildScroller(xmlData.image); //rather than trace the xmlList, we send it to our buildScroller function

}

/////Build Scroller MovieClip to Contain Each Image

var scroller:MovieClip = new MovieClip();

var padding:Number = 5;//creating a var for padding to be used later on in easier calculations

//making the mask+boundaries

scroller.mask = maskRctngl;

var maskBorders:Number = 93;// distance from stage borders 88 px + padding 5 px

this.addChild(scroller);

scroller.y = 645;

scroller.x = maskBorders;

var thumbSmall:Number = 1;//setting up scale Tween on rollover

var thumbLarge:Number = 1.05;//setting up scale Tween on rollover

/////

/////Parse XML

//build scroller from xml

function buildScroller(imageList:XMLList):void{

    for (var item:uint = 0; item<imageList.length();item++) {

        var thisOne:MovieClip = new MovieClip();

        //outline

        var thumbFadeOut:Number = .3;//setting Border Tweens//doesn't work with TweenMax transitions

        var thumbFadeIn:Number = .7;//setting Border Tweens//doesn't work with TweenMax transitions

        var blackBox:Sprite = new Sprite();

        blackBox.graphics.beginFill(0xFFFFFF);

        blackBox.graphics.drawRect(-1, -1, 62, 92);

        blackBox.alpha = thumbFadeOut;//setting Border Tweens

        thisOne.addChild(blackBox);

        thisOne.blackBox = blackBox;//setting Border Tweens

        thisOne.x = thisOne.myx = (60 + padding) *item;

        thisOne.itemNum = item;

        thisOne.title = imageList[item].attribute("title");

        thisOne.link = imageList[item].attribute("url");

        thisOne.src = imageList[item].attribute("src");

        thisOne.alpha = 0;//makes all thumb images at alpha=0 before they are fully loaded

        //Loading and Adding the Images

        //image container

        var thisThumb:MovieClip = new MovieClip();

        //add image

        var ldr:Loader = new Loader();

        var urlReq:URLRequest = new URLRequest(thisOne.src);

        ldr.load(urlReq);

        //assign event listeners for Loader

        ldr.contentLoaderInfo.addEventListener(Event.COMPLETE,completeHandler_AppPopUps);//tells us when the loading is complete

        ldr.contentLoaderInfo.addEventListener(IOErrorEvent.IO_ERROR, errorHandler_AppPopUps);//tells us if there are any typo errors when the loading is complete

        thisThumb.addChild(ldr);

        thisOne.addChild(thisThumb);

        //create listeners for this thumb

        thisOne.buttonMode = true;//makes boxes act as buttons

        thisOne.addEventListener(MouseEvent.CLICK, clickScrollerItem_AppPopUps);//makes boxes act as buttons

        thisOne.addEventListener(MouseEvent.MOUSE_OVER, overScrollerItem_AppPopUps);//traces the title when the mouse is over the bounding box in the Output Panel

        thisOne.addEventListener(MouseEvent.MOUSE_OUT, outScrollerItem_AppPopUps);//traces the title when the mouse is out the bounding box in the Output Panel

        //add item

        scroller.addChild(thisOne);

    }

    scroller.addEventListener(Event.ENTER_FRAME, moveScrollerThumbs);//adding movement on mouse position

}