diff --git a/youtube_dl/extractor/youtube.py b/youtube_dl/extractor/youtube.py
index 8b6e591a4..329690742 100644
--- a/youtube_dl/extractor/youtube.py
+++ b/youtube_dl/extractor/youtube.py
@@ -417,6 +417,22 @@ class YoutubeIE(YoutubeBaseInfoExtractor, SubtitlesInfoExtractor):
                 'upload_date': '20140605',
             },
         },
+        # video_info is None (https://github.com/rg3/youtube-dl/issues/4421)
+        {
+            'url': '__2ABJjxzNo',
+            'info_dict': {
+                'id': '__2ABJjxzNo',
+                'ext': 'mp4',
+                'upload_date': '20100430',
+                'uploader_id': 'deadmau5',
+                'description': 'md5:12c56784b8032162bb936a5f76d55360',
+                'uploader': 'deadmau5',
+                'title': 'Deadmau5 - Some Chords (HD)',
+            },
+            'expected_warnings': [
+                'DASH manifest missing',
+            ]
+        }
     ]
 
     def __init__(self, *args, **kwargs):
@@ -666,6 +682,45 @@ def _extract_annotations(self, video_id):
         url = 'https://www.youtube.com/annotations_invideo?features=1&legacy=1&video_id=%s' % video_id
         return self._download_webpage(url, video_id, note='Searching for annotations.', errnote='Unable to download video annotations.')
 
+    def _parse_dash_manifest(self, video_id, dash_manifest_url):
+        def decrypt_sig(mobj):
+            s = mobj.group(1)
+            dec_s = self._decrypt_signature(s, video_id, player_url, age_gate)
+            return '/signature/%s' % dec_s
+        dash_manifest_url = re.sub(r'/s/([\w\.]+)', decrypt_sig, dash_manifest_url)
+        dash_doc = self._download_xml(
+            dash_manifest_url, video_id,
+            note='Downloading DASH manifest',
+            errnote='Could not download DASH manifest')
+
+        formats = []
+        for r in dash_doc.findall('.//{urn:mpeg:DASH:schema:MPD:2011}Representation'):
+            url_el = r.find('{urn:mpeg:DASH:schema:MPD:2011}BaseURL')
+            if url_el is None:
+                continue
+            format_id = r.attrib['id']
+            video_url = url_el.text
+            filesize = int_or_none(url_el.attrib.get('{http://youtube.com/yt/2012/10/10}contentLength'))
+            f = {
+                'format_id': format_id,
+                'url': video_url,
+                'width': int_or_none(r.attrib.get('width')),
+                'tbr': int_or_none(r.attrib.get('bandwidth'), 1000),
+                'asr': int_or_none(r.attrib.get('audioSamplingRate')),
+                'filesize': filesize,
+                'fps': int_or_none(r.attrib.get('frameRate')),
+            }
+            try:
+                existing_format = next(
+                    fo for fo in formats
+                    if fo['format_id'] == format_id)
+            except StopIteration:
+                f.update(self._formats.get(format_id, {}))
+                formats.append(f)
+            else:
+                existing_format.update(f)
+        return formats
+
     def _real_extract(self, url):
         proto = (
             'http' if self._downloader.params.get('prefer_insecure', False)
@@ -943,51 +998,19 @@ def _map_to_format_list(urlmap):
 
         # Look for the DASH manifest
         if self._downloader.params.get('youtube_include_dash_manifest', True):
-            try:
-                # The DASH manifest used needs to be the one from the original video_webpage.
-                # The one found in get_video_info seems to be using different signatures.
-                # However, in the case of an age restriction there won't be any embedded dashmpd in the video_webpage.
-                # Luckily, it seems, this case uses some kind of default signature (len == 86), so the
-                # combination of get_video_info and the _static_decrypt_signature() decryption fallback will work here.
-                dash_manifest_url = video_info.get('dashmpd')[0]
-
-                def decrypt_sig(mobj):
-                    s = mobj.group(1)
-                    dec_s = self._decrypt_signature(s, video_id, player_url, age_gate)
-                    return '/signature/%s' % dec_s
-                dash_manifest_url = re.sub(r'/s/([\w\.]+)', decrypt_sig, dash_manifest_url)
-                dash_doc = self._download_xml(
-                    dash_manifest_url, video_id,
-                    note='Downloading DASH manifest',
-                    errnote='Could not download DASH manifest')
-                for r in dash_doc.findall('.//{urn:mpeg:DASH:schema:MPD:2011}Representation'):
-                    url_el = r.find('{urn:mpeg:DASH:schema:MPD:2011}BaseURL')
-                    if url_el is None:
-                        continue
-                    format_id = r.attrib['id']
-                    video_url = url_el.text
-                    filesize = int_or_none(url_el.attrib.get('{http://youtube.com/yt/2012/10/10}contentLength'))
-                    f = {
-                        'format_id': format_id,
-                        'url': video_url,
-                        'width': int_or_none(r.attrib.get('width')),
-                        'tbr': int_or_none(r.attrib.get('bandwidth'), 1000),
-                        'asr': int_or_none(r.attrib.get('audioSamplingRate')),
-                        'filesize': filesize,
-                        'fps': int_or_none(r.attrib.get('frameRate')),
-                    }
-                    try:
-                        existing_format = next(
-                            fo for fo in formats
-                            if fo['format_id'] == format_id)
-                    except StopIteration:
-                        f.update(self._formats.get(format_id, {}))
-                        formats.append(f)
-                    else:
-                        existing_format.update(f)
-
-            except (ExtractorError, KeyError) as e:
-                self.report_warning('Skipping DASH manifest: %r' % e, video_id)
+            dash_mpd = video_info.get('dashmpd')
+            if not dash_mpd:
+                self.report_warning('%s: DASH manifest missing' % video_id)
+            else:
+                dash_manifest_url = dash_mpd[0]
+                try:
+                    dash_formats = self._parse_dash_manifest(
+                        video_id, dash_manifest_url)
+                except (ExtractorError, KeyError) as e:
+                    self.report_warning(
+                        'Skipping DASH manifest: %r' % e, video_id)
+                else:
+                    formats.extend(dash_formats)
 
         self._sort_formats(formats)