that may be progress so
delete the onload and replace with
mydata.onload = function() {
for (c=0; c<=_root.mydata.total; c++) {
removeMovieClip("_root.holder"+c);
for (c=0; c<=mydata.total; c++) {
// make a new holder for each msg and set the position
thisx = eval("mydata.dbmcx"+c);
thisy = eval("mydata.dbmcy"+c);
setProperty(holder, _x, thisx);
setProperty(holder, _y, thisy);
setProperty(_root.holder, _visible, 0);
duplicateMovieClip(_root.holder, "holder"+c, c+15);
// set the apropriate icon
thisico = eval("mydata.ico"+c);
set("_root.holder"+c+".ico", thisico);
// load the variables into the new movieclip
thisdate = eval("mydata.date"+c);
thisname = eval("mydata.name"+c);
thismail = eval("mydata.mail"+c);
thismsg = eval("mydata.msg"+c);
thisid = eval("mydata.id"+c);
thismarked = eval("mydata.marked"+c);
set("_root.holder"+c+".content.tdate", thisdate);
set("_root.holder"+c+".content.name", thisname);
set("_root.holder"+c+".content.mail", thismail);
set("_root.holder"+c+".content.msg", thismsg);
set("_root.holder"+c+".content.deletemc.id", thisid);
set("_root.holder"+c+".content.markmc.id", thisid);
set("_root.holder"+c+".id", c);
set("_root.holder"+c+".marked", thismarked);
}