IW 15.5.10 Sendfile

Hi,

After installing Delphi 12 Version 29.0.51511.6924 and IW 15.5.10


I has written a csv file like this: 
  { Create file }
  xFileName:=UserSession.UserId + '_1' + ExtractFileName('SaveAs') + '.csv';
  xPath:=gServerController.ContentPath  + 'Files\XIBFiles\' + xFileName;
  UserSession.ViewThisFile:=xPath;
  DeleteFile(UserSession.ViewThisFile);
  ZnfStreamW := TStreamWriter.Create(UserSession.ViewThisFile, False, TEncoding.Default);

.....
.....
.....

      ZnfStreamW.WriteLine(Line);
      dm.FDQrySaveAs.Next;
    end;
    dm.FDQrySaveAs.Close;
    WebApplication.SendFile(UserSession.ViewThisFile, False, '', ExtractFileName(UserSession.ViewThisFile));
  finally
    FreeAndNil(ZnfStreamW);    { Close and Free the writer }
  end;

This has worked perfectly before, but now the file is mysterious converted to a html fil

&t!DOCTYPE HTML&t
&thtml lang="en"&t
&thead&t
&tmeta charset="utf-8"&t
&ttitle&tXIB - Web Watch Dog: WWD (OpusCapita Solutions)&t/title&t
&tmeta name="generator" content="IntraWeb v15.5.10 Serial 202440434"&t



&tlink href="/wwd/isapixibwwd.dll/$/css/IWBase__2933165573.css" rel="stylesheet"&t
&tscript nonce="yIJCVKoI+fDI9a5EoWWulrCEZwY"&t
var GURLBase="/wwd/isapixibwwd.dll/$/", GAppID="AeUrkFJfeLMC7BviU77qNcKmFGq", GTrackID=12
function doOnReady(f){
  var d = document
  if (d.readyState!="loading") f()
  else if (d.addEventListener) d.addEventListener("DOMContentLoaded", f)
  else d.attachEvent("onreadystatechange", function(){if (d.readyState=="complete") f()
}
&t/script&t
&tscript src="/wwd/isapixibwwd.dll/$/js/IWLib__1925002372.js"&t&t/script&t
&tscript src="/wwd/isapixibwwd.dll/$/js/IWBase__702901585.js"&t&t/script&t
&tscript src="/wwd/isapixibwwd.dll/$/js/IWGecko__3425527816.js"&t&t/script&t
&tscript nonce="yIJCVKoI+fDI9a5EoWWulrCEZwY"&t