Debugging MusicXML import failures

I’ve downloaded a couple of MusicXML files from cpdl.org that fail to import in Dorico (and also fail in MuseScore). Unfortunately, Dorico gives completely unhelpful error message: “Error opening file: invalid file format”. MS gives something similar.

The structure of the two files looks fine and the XML validates (they’re uncompressed). Is there any way to get Dorico to provide more information about what it doesn’t like about the files?

In case it’s something obvious, here’s the header from one of the files (full file is available here):

<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
<!DOCTYPE score-partwise PUBLIC "-//Recordare//DTD MusicXML 3.0 Partwise//EN" "http://www.musicxml.org/dtds/partwise.dtd">
<score-partwise>

  <work>
    <work-title>Alma Redemptoris Mater</work-title>
  </work>

  <identification>
    <creator type="composer">Guillaume Dufay</creator>
    <encoding>
      <software>Mozart 15.0.11.0</software>
      <supports attribute="new-system" element="print" type="yes" value="yes"/>
      <supports attribute="new-page" element="print" type="yes" value="yes"/>
    </encoding>
  </identification>

  <defaults>
    <scaling>
      <millimeters>60</millimeters>
      <tenths>400</tenths>
    </scaling>
    <page-layout>
      <page-height>1950</page-height>
      <page-width>1369</page-width>
      <page-margins type="odd">
        <left-margin>98</left-margin>
        <right-margin>98</right-margin>
        <top-margin>0</top-margin>
        <bottom-margin>0</bottom-margin>
      </page-margins>
      <page-margins type="even">
        <left-margin>98</left-margin>
        <right-margin>98</right-margin>
        <top-margin>60</top-margin>
        <bottom-margin>0</bottom-margin>
      </page-margins>
    </page-layout>
    <system-layout>
      <system-margins>
        <left-margin>0</left-margin>
        <right-margin>0</right-margin>
      </system-margins>
      <system-distance>138</system-distance>
      <top-system-distance>43</top-system-distance>
    </system-layout>
  </defaults>

  <credit page="1">
    <credit-words default-x="697" default-y="1842" font-size="15.8" halign="center" justify="left" valign="bottom">Alma Redemptoris Mater</credit-words>
  </credit>

  <credit page="1">
    <credit-words default-x="1236" default-y="1800" font-size="10.9" halign="center" justify="left" valign="bottom">Guillaume Dufay</credit-words>
  </credit>

  <part-list>
    <score-part id="P1">
      <part-name>Part_1</part-name>
      <part-name-display print-object="no"/>
      <score-instrument id="I1-ffff-0-49">
        <instrument-name>Inconnu</instrument-name>
      </score-instrument>
      <midi-instrument id="I1-ffff-0-49">
        <midi-channel>2</midi-channel>
        <midi-program>74</midi-program>
        <volume>100</volume>
      </midi-instrument>
    </score-part>
    <score-part id="P2">
      <part-name>Part_2</part-name>
      <part-name-display print-object="no"/>
      <score-instrument id="I2-2040-d12-49">
        <instrument-name>Tenor</instrument-name>
        <instrument-abbreviation>Ten.</instrument-abbreviation>
      </score-instrument>
      <midi-instrument id="I2-2040-d12-49">
        <midi-channel>3</midi-channel>
        <midi-program>74</midi-program>
        <volume>100</volume>
      </midi-instrument>
    </score-part>
    <score-part id="P3">
      <part-name>Part_3</part-name>
      <part-name-display print-object="no"/>
      <score-instrument id="I3-2000-0-49">
        <instrument-name>Bass</instrument-name>
        <instrument-abbreviation>Bs.</instrument-abbreviation>
      </score-instrument>
      <midi-instrument id="I3-2000-0-49">
        <midi-channel>4</midi-channel>
        <midi-program>74</midi-program>
        <volume>100</volume>
      </midi-instrument>
    </score-part>
  </part-list>

   <!-- (guts removed) -->

</score-partwise>

The file is fine, but it has the wrong file extension. If you change it from .mxl to .musicxml or even just to .xml, you will be able to open it in Dorico.

Wow, easy fix. Thanks for the quick response!