Every time I edit my .html file on FTP file manager and save it, I return to find that it has been modified. For instance, here is the first few lines of code I saved:

<!-- configurable script -->
<script type="text/javascript">
theimage = new Array();

and here is what it changed to when I returned to edit.

<html><TABLE border=0 cellSpacing=0 width="100%" height="25%" valign="center" halign="center">

The program completely deleted an entire block of javascript. Why would the file manager edit my html?