diff --git a/lib/db/upgrade.php b/lib/db/upgrade.php
index 32298db70a0..7ce3c1e8d93 100644
--- a/lib/db/upgrade.php
+++ b/lib/db/upgrade.php
@@ -2194,8 +2194,11 @@ function xmldb_main_upgrade($oldversion) {
             $DB->delete_records('competency_userevidencecomp', ['userevidenceid' => $userevidence->id]);
             $DB->delete_records('competency_userevidence', ['id' => $userevidence->id]);
 
-            $context = context_user::instance($userevidence->userid);
-            $fs->delete_area_files($context->id, 'core_competency', 'userevidence', $userevidence->id);
+            if ($record = $DB->get_record('context', ['contextlevel' => CONTEXT_USER, 'instanceid' => $userevidence->userid],
+                    '*', IGNORE_MISSING)) {
+                // Delete all orphaned user evidences files.
+                $fs->delete_area_files($record->id, 'core_competency', 'userevidence', $userevidence->userid);
+            }
         }
 
         $sql = "SELECT cp.id
@@ -2527,5 +2530,24 @@ function xmldb_main_upgrade($oldversion) {
         upgrade_main_savepoint(true, 2020061501.04);
     }
 
+    if ($oldversion < 2020061501.08) {
+        // Delete all user evidence files from users that have been deleted.
+        $sql = "SELECT DISTINCT f.*
+                  FROM {files} f
+             LEFT JOIN {context} c ON f.contextid = c.id
+             LEFT JOIN {user} u ON c.instanceid = u.id
+                 WHERE f.component = :component
+                   AND f.filearea = :filearea
+                   AND u.deleted = 1";
+        $stalefiles = $DB->get_records_sql($sql, ['component' => 'core_competency', 'filearea' => 'userevidence']);
+
+        $fs = get_file_storage();
+        foreach ($stalefiles as $stalefile) {
+            $fs->get_file_instance($stalefile)->delete();
+        }
+
+        upgrade_main_savepoint(true, 2020061501.08);
+    }
+
     return true;
 }
diff --git a/version.php b/version.php
index e2315b2c45f..ae7836198fd 100644
--- a/version.php
+++ b/version.php
@@ -29,7 +29,7 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$version  = 2020061501.07;              // 20200615      = branching date YYYYMMDD - do not modify!
+$version  = 2020061501.08;              // 20200615      = branching date YYYYMMDD - do not modify!
                                         //         RR    = release increments - 00 in DEV branches.
                                         //           .XX = incremental changes.
 $release  = '3.9.1+ (Build: 20200814)'; // Human-friendly version name