Here is what I see (error message) when I attempt to download QSO's from LOTW:
Returned results are not ADIF. Possible reasons include bad/user password. Check the returned HTML for error messages.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<HTML><HEAD><TITLE>ARRL's Logbook of the World</TITLE>
<link rel="stylesheet" href="/js/jquery-ui-1.11.4.custom/jquery-ui.min.css" type="text/css">
<link rel="stylesheet" href="/js/jquery-ui-1.11.4.custom/jquery-ui.structure.min.css" type="text/css">
<link rel="stylesheet" href="/js/jquery-ui-1.11.4.custom/jquery-ui.theme.min.css" type="text/css">
<link rel="stylesheet" href="/css/lotw/lotw.password.checker.css">
<link rel="stylesheet" href="/css/lotw/lotw.css" type="text/css">
<script type="text/javascript" src="/js/jquery-1.11.3.min.js"></script>
<script type="text/javascript" src="/js/jquery-migrate-1.2.1.min.js"></script>
<script type="text/javascript" src="/js/jquery-ui-1.11.4.custom/jquery-ui.min.js"></script>
<script type="text/javascript" src="/js/dialog-base.js"></script>
<script type="text/javascript" src="/js/dialog-lotw.js"></script>
<script type="text/javascript" src="/js/dialog-search-help.js"></script>
<script type="text/javascript" src="/js/api-base.js"></script>
<script type="text/javascript" src="/js/site-search.js"></script>
<script type="text/javascript">
jQuery( document ).tooltip();
</script>
<!-- uncomment the following to enable Google Analytics on the production web server ONLY -->
<script type="text/javascript" src="/js/ga.js"></script>
<script language="javascript" type="text/javascript">
jQuery(document).ready(function() {
dlgLOTW.ready();
});
</script>
</HEAD>
<BODY LINK="#0000FF" VLINK="#0000FF" BGCOLOR="#FFFFFF">
<table cellspacing=0 border=0 cellpadding=0 class='pagehead'>
<tr valign="top">
<td rowspan=2><img src="/lotw-logo.jpg" width=333 height=220
border=0 alt="Logbook of the World"><br>
<A HREF="https://p1k.arrl.org/adredir.php3?id=5" TARGET="ARRLWebAdWindow"><IMG SRC="https://p1k.arrl.org/adbanners/Yaesu-PS8.gif" ALT="Yaesu -- Choice of the World's top DX'ers -- Ad" WIDTH="468" HEIGHT="60" BORDER="0" style="margin:5px;border:solid #888 1px"></A>
</td>
<td width="100%">
<TABLE BORDER=0 CELLPADDING=3 CELLSPACING=0 WIDTH="100%" class='userhead'>
<TR>
<TD align="right">Today is Thu, 10 Sep 2020 UTC</TD>
</TR>
<TR>
<TD align="right"><A HREF="/lotw/login"><b>Log On</b></A></TD>
</TR>
</TABLE>
<div style='height:120px;'> </div>
<table border=0 cellpadding=0 cellspacing=0 width="100%">
<tr>
<td align='right'><div style='padding-right:10px;'><label id='data_help_search_q_lbl' for='data_help_search_q'>Search Help: </label><input type='text' id='data_help_search_q' name='data_help_search_q' value='Search Help'/>
<button type='button' id="help_search_btn">Search</button></div>
</td>
</tr>
</table>
</td>
</tr>
<tr valign="bottom">
<td></td>
</tr>
</table>
<SCRIPT type="text/javascript">
// This is needed for older browsers (like < IE 10) which
// don't gronk the autofocus attribute on the input element
window.onload = function() {
var input = document.getElementById("username").focus();
}
</SCRIPT>
<H3>Log on to Logbook of the World</H3>
<P>
<I>Note:</I> You must have been issued a certificate before you can log on to the LoTW site.
<P>
<FORM ACTION="/lotwuser/lotwreport.adi" METHOD="post">
<table cellspacing=0 border=0 cellpadding=3>
<tr>
<td align="right"><b>Username:</b></td>
<td><INPUT TYPE="text" id="username" name="login" size=12 autofocus></td>
</tr>
<tr>
<td align="right"><b>Password:</b></td>
<td><INPUT TYPE="password" name="password" size=12> Note: This is <b>not</b> the password
sent to US amateurs via postcard!</td>
</tr>
<tr>
<td></td>
<td><a href="/lotw/forgot">Forgot password?</a>
</tr>
<tr>
<td></td>
<td><INPUT TYPE="submit" VALUE="Log On"></td>
</tr>
</table>
<INPUT type="hidden" name="acct_sel" value="">
<INPUT type="hidden" name="qso_owncall" value="">
<INPUT type="hidden" name="qso_qsl" value="yes">
<INPUT type="hidden" name="qso_qsldetail" value="yes">
<INPUT type="hidden" name="qso_qslsince" value="1900-01-01">
<INPUT type="hidden" name="qso_query" value="1">
<INPUT type="hidden" name="qso_withown" value="yes">
<INPUT type="hidden" name="thisForm" value="login">
</FORM>
<P>
<I>Username/password incorrect</I>
<P>
Try entering your password in all lower case. If that doesn't work, please contact the Help desk via e-mail at
LoTW-help@arrl.org or other methods at <A HREF="/lotw-help/GettingHelp/" target="_blank">Getting Help</A>
<P>
Your browser must support cookies and be set to accept cookies from
lotw.arrl.org in order to log in.
<p>Not a member of Logbook of the World? <a href="http://www.arrl.org/quick-start">Get started today!</a></p>
<p><a href="http://www.arrl.org">ARRL website</a></p>
<br clear="all">
<table width="100%">
<TR>
<TD width="50%" align="left">
<P style="font-size:80%">
Copyright 2020 American Radio Relay League, Inc.<BR>
All Rights Reserved
</p>
</TD>
<TD width="50%" align="right" valign="bottom">
<P style="font-size:80%">
<a href="http://www.arrl.org/privacy-policy" target="_blank">Terms of Use/Privacy Policy</a>
</p>
</TD>
</TR>
</table>
</BODY></HTML>
