Modify the redirct.php file, line 153(?)
It says:
header("Location: $redirect_url");
Change to:
echo "<html><head><META HTTP-EQUIV=\"Refresh\" CONTENT=\"0; URL="" href="">
Here is where I found the answers:
http://www.squirrelmail.org/wiki/en_US/InstallingSquirrelMailWindowsIIS (bottom half of page)
and
http://sourceforge.net/tracker/index.php?func=detail&aid=542724&group_id=311&atid=100311
-Christopher
