diff --git a/mod/data/classes/local/importer/preset_importer.php b/mod/data/classes/local/importer/preset_importer.php
index 5b898290845..c5e48682847 100644
--- a/mod/data/classes/local/importer/preset_importer.php
+++ b/mod/data/classes/local/importer/preset_importer.php
@@ -19,6 +19,7 @@ namespace mod_data\local\importer;
 use mod_data\manager;
 use mod_data\preset;
 use stdClass;
+use html_writer;
 
 /**
  * Abstract class used for data preset importers
@@ -212,7 +213,7 @@ abstract class preset_importer {
      * @return bool Wether the importing has been successful.
      */
     public function import(bool $overwritesettings): bool {
-        global $DB;
+        global $DB, $OUTPUT;
 
         $params = $this->get_preset_settings();
         $settings = $params->settings;
@@ -252,7 +253,12 @@ abstract class preset_importer {
                     unset($fieldobject);
                 } else {
                     /* Make a new field */
-                    include_once("field/$newfield->type/field.class.php");
+                    $filepath = "field/$newfield->type/field.class.php";
+                    if (!file_exists($filepath)) {
+                        $missingfieldtypes[] = $newfield->name;
+                        continue;
+                    }
+                    include_once($filepath);
 
                     if (!isset($newfield->description)) {
                         $newfield->description = '';
@@ -263,6 +269,9 @@ abstract class preset_importer {
                     unset($fieldclass);
                 }
             }
+            if (!empty($missingfieldtypes)) {
+                echo $OUTPUT->notification(get_string('missingfieldtypeimport', 'data') . html_writer::alist($missingfieldtypes));
+            }
         }
 
         // Get rid of all old unused data.
diff --git a/mod/data/classes/output/template_editor_tools.php b/mod/data/classes/output/template_editor_tools.php
index 54915c95c87..5302bfa0fed 100644
--- a/mod/data/classes/output/template_editor_tools.php
+++ b/mod/data/classes/output/template_editor_tools.php
@@ -84,6 +84,9 @@ class template_editor_tools implements templatable, renderable {
         $taglist = [];
         $fields = $this->manager->get_fields();
         foreach ($fields as $field) {
+            if ($field->type === 'unknown') {
+                continue;
+            }
             $fieldname = $field->get_name();
             $taglist["[[$fieldname]]"] = $fieldname;
         }
@@ -105,6 +108,9 @@ class template_editor_tools implements templatable, renderable {
         // Field IDs.
         $fields = $this->manager->get_fields();
         foreach ($fields as $field) {
+            if ($field->type === 'unknown') {
+                continue;
+            }
             $fieldname = $field->get_name();
             $taglist["[[$fieldname#id]]"] = "$fieldname id";
         }
diff --git a/mod/data/classes/search/entry.php b/mod/data/classes/search/entry.php
index dc65a5751e7..95ee8a0a95c 100644
--- a/mod/data/classes/search/entry.php
+++ b/mod/data/classes/search/entry.php
@@ -299,6 +299,10 @@ class entry extends \core_search\base_mod {
 
         foreach ($filteredcontents as $content) {
             $classname = $this->get_field_class_name($content->fieldtype);
+            if (!$classname) {
+                $content->addtemplateposition = -1;
+                continue;
+            }
             $content->priority = $classname::get_priority();
             $content->addtemplateposition = strpos($template, '[['.$content->fldname.']]');
         }
@@ -346,16 +350,22 @@ class entry extends \core_search\base_mod {
     }
 
     /**
-     * Returns the class name for that field type and includes it.
+     * Returns the class name for the given field type and includes it.
      *
      * @param string $fieldtype
-     * @return string
+     * @return string|null It will return the class name or null if the field type is not available.
      */
     protected function get_field_class_name($fieldtype) {
         global $CFG;
 
         $fieldtype = trim($fieldtype);
-        require_once($CFG->dirroot . '/mod/data/field/' . $fieldtype . '/field.class.php');
+
+        $fieldpath = $CFG->dirroot . '/mod/data/field/' . $fieldtype . '/field.class.php';
+        if (!file_exists($fieldpath)) {
+            return null;
+        }
+
+        require_once($fieldpath);
         return 'data_field_' . $fieldtype;
     }
 
diff --git a/mod/data/classes/template.php b/mod/data/classes/template.php
index fec7402f261..96c2097e389 100644
--- a/mod/data/classes/template.php
+++ b/mod/data/classes/template.php
@@ -850,7 +850,17 @@ class template {
                         $errors .= $renderer->notification($notification);
                     }
                 }
-                $replacements[] = $errors . $field->display_add_field($entryid, $entrydata);
+                $fielddisplay = '';
+                if ($field->type === 'unknown') {
+                    if ($this->canmanageentries) { // Display notification for users that can manage entries.
+                        $errors .= $renderer->notification(get_string('missingfieldtype', 'data',
+                        (object)['name' => $field->field->name]));
+                    }
+                } else {
+                    $fielddisplay = $field->display_add_field($entryid, $entrydata);
+                }
+
+                $replacements[] = $errors . $fielddisplay;
             }
 
             // Replace the field id tag.
diff --git a/mod/data/field.php b/mod/data/field.php
index 156c753d7a2..b5f02983d2f 100644
--- a/mod/data/field.php
+++ b/mod/data/field.php
@@ -260,9 +260,15 @@ switch ($mode) {
                 // Print confirmation message.
                 $field = data_get_field_from_id($fid, $data);
 
-                echo $OUTPUT->confirm('<strong>'.$field->name().': '.$field->field->name.'</strong><br /><br />'. get_string('confirmdeletefield','data'),
-                             'field.php?d='.$data->id.'&mode=delete&fid='.$fid.'&confirm=1',
-                             'field.php?d='.$data->id);
+                if ($field->type === 'unknown') {
+                    $fieldtypename = get_string('unknown', 'data');
+                } else {
+                    $fieldtypename = $field->name();
+                }
+                echo $OUTPUT->confirm('<strong>'.$fieldtypename.': '.$field->field->name.'</strong><br /><br />'.
+                            get_string('confirmdeletefield', 'data'),
+                            'field.php?d='.$data->id.'&mode=delete&fid='.$fid.'&confirm=1',
+                            'field.php?d='.$data->id);
 
                 echo $OUTPUT->footer();
                 exit;
@@ -317,6 +323,9 @@ $plugins = core_component::get_plugin_list('datafield');
 $menufield = array();
 
 foreach ($plugins as $plugin=>$fulldir){
+    if (!is_dir($fulldir)) {
+        continue;
+    }
     $menufield[$plugin] = get_string('pluginname', 'datafield_'.$plugin);    //get from language files
 }
 asort($menufield);    //sort in alphabetical order
@@ -360,6 +369,7 @@ if (($mode == 'new') && (!empty($newtype))) { // Adding a new field.
         $table->wrap = array(false,false,false,false);
 
         if ($fff = $DB->get_records('data_fields', array('dataid'=>$data->id),'id')){
+            $missingfieldtypes = [];
             foreach ($fff as $ff) {
 
                 $field = data_get_field($ff, $data);
@@ -378,15 +388,30 @@ if (($mode == 'new') && (!empty($newtype))) { // Adding a new field.
                     'mode'      => 'delete',
                 ));
 
-                $table->data[] = array(
-                    html_writer::link($displayurl, $field->field->name),
-                    $field->image() . '&nbsp;' . $field->name(),
+                // It display a notification when the field type does not exist.
+                $deletelink = html_writer::link($deleteurl, $OUTPUT->pix_icon('t/delete', get_string('delete')));
+                $editlink = html_writer::link($displayurl, $OUTPUT->pix_icon('t/edit', get_string('edit')));
+                if ($field->type === 'unknown') {
+                    $missingfieldtypes[] = $field->field->name;
+                    $fieldnamedata = $field->field->name;
+                    $fieltypedata = $field->field->type;
+                    $fieldlinkdata = $deletelink;
+                } else {
+                    $fieldnamedata = html_writer::link($displayurl, $field->field->name);
+                    $fieltypedata = $field->image() . '&nbsp;' . $field->name();
+                    $fieldlinkdata = $editlink . '&nbsp;' . $deletelink;
+                }
+
+                $table->data[] = [
+                    $fieldnamedata,
+                    $fieltypedata,
                     $field->field->required ? get_string('yes') : get_string('no'),
                     shorten_text($field->field->description, 30),
-                    html_writer::link($displayurl, $OUTPUT->pix_icon('t/edit', get_string('edit'))) .
-                        '&nbsp;' .
-                        html_writer::link($deleteurl, $OUTPUT->pix_icon('t/delete', get_string('delete'))),
-                );
+                    $fieldlinkdata
+                ];
+            }
+            if (!empty($missingfieldtypes)) {
+                echo $OUTPUT->notification(get_string('missingfieldtypes', 'data') . html_writer::alist($missingfieldtypes));
             }
         }
         echo html_writer::table($table);
diff --git a/mod/data/lang/en/data.php b/mod/data/lang/en/data.php
index 9ceef0f8d69..2f95d831a5d 100644
--- a/mod/data/lang/en/data.php
+++ b/mod/data/lang/en/data.php
@@ -238,6 +238,11 @@ $string['invalidfieldid'] = 'Field ID is incorrect';
 $string['invalidfieldname'] = 'Please choose another name for this field';
 $string['invalidfieldtype'] = 'Field type is incorrect';
 $string['invalidid'] = 'Incorrect data ID';
+$string['missingfieldtype'] = 'Field type for {$a->name} not found';
+$string['missingfieldtypes'] = 'The following fields do not have their corresponding field types installed and will not be included in the forms when adding or editing entries.
+ Their labels may still show on the form, so please update the "Add entry template" accordingly:';
+$string['missingfieldtypeimport'] = 'The following fields were not imported because their corresponding field types are not installed:';
+$string['unknown'] = 'Unknown field';
 $string['invalidpreset'] = '{$a} is not a preset.';
 $string['invalidrecord'] = 'Incorrect record';
 $string['invalidurl'] = 'The URL you just entered is not valid';
diff --git a/mod/data/lib.php b/mod/data/lib.php
index 9643740463f..8760c2e23eb 100644
--- a/mod/data/lib.php
+++ b/mod/data/lib.php
@@ -400,6 +400,12 @@ class data_field_base {     // Base class for Database Field Types (see field/*/
         if (empty($this->field)) {   // No field has been defined yet, try and make one
             $this->define_default_field();
         }
+
+        // Throw an exception if field type doen't exist. Anyway user should never access to edit a field with an unknown fieldtype.
+        if ($this->type === 'unknown') {
+            throw new \moodle_exception(get_string('missingfieldtype', 'data', (object)['name' => $this->field->name]));
+        }
+
         echo $OUTPUT->box_start('generalbox boxaligncenter boxwidthwide');
 
         echo '<form id="editfield" action="'.$CFG->wwwroot.'/mod/data/field.php" method="post">'."\n";
@@ -417,7 +423,14 @@ class data_field_base {     // Base class for Database Field Types (see field/*/
 
         echo $OUTPUT->heading($this->name(), 3);
 
-        require_once($CFG->dirroot.'/mod/data/field/'.$this->type.'/mod.html');
+
+        $filepath = $CFG->dirroot.'/mod/data/field/'.$this->type.'/mod.html';
+
+        if (!file_exists($filepath)) {
+            throw new \moodle_exception(get_string('missingfieldtype', 'data', (object)['name' => $this->field->name]));
+        } else {
+            require_once($filepath);
+        }
 
         echo html_writer::start_div('mt-3');
         echo html_writer::tag('input', null, array('type' => 'submit', 'value' => $savebutton,
@@ -916,7 +929,12 @@ function data_get_field_from_id($fieldid, $data){
 function data_get_field_new($type, $data) {
     global $CFG;
 
-    require_once($CFG->dirroot.'/mod/data/field/'.$type.'/field.class.php');
+    $filepath = $CFG->dirroot.'/mod/data/field/'.$type.'/field.class.php';
+    // It should never access this method if the subfield class doesn't exist.
+    if (!file_exists($filepath)) {
+        throw new \moodle_exception('invalidfieldtype', 'data');
+    }
+    require_once($filepath);
     $newfield = 'data_field_'.$type;
     $newfield = new $newfield(0, $data);
     return $newfield;
@@ -928,20 +946,24 @@ function data_get_field_new($type, $data) {
  * input: $param $field - record from db
  *
  * @global object
- * @param object $field
- * @param object $data
- * @param object $cm
- * @return data_field_base
+ * @param stdClass $field the field record
+ * @param stdClass $data the data instance
+ * @param stdClass|null $cm optional course module data
+ * @return data_field_base the field object instance or data_field_base if unkown type
  */
 function data_get_field($field, $data, $cm=null) {
     global $CFG;
-
-    if ($field) {
-        require_once('field/'.$field->type.'/field.class.php');
-        $newfield = 'data_field_'.$field->type;
-        $newfield = new $newfield($field, $data, $cm);
-        return $newfield;
+    if (!isset($field->type)) {
+        return new data_field_base($field);
     }
+    $filepath = $CFG->dirroot.'/mod/data/field/'.$field->type.'/field.class.php';
+    if (!file_exists($filepath)) {
+        return new data_field_base($field);
+    }
+    require_once($filepath);
+    $newfield = 'data_field_'.$field->type;
+    $newfield = new $newfield($field, $data, $cm);
+    return $newfield;
 }
 
 
@@ -1764,6 +1786,10 @@ function data_print_preference_form($data, $perpage, $search, $sort='', $order='
         $fieldname = preg_quote($fieldname, '/');
         $patterns[] = "/\[\[$fieldname\]\]/i";
         $searchfield = data_get_field_from_id($field->field->id, $data);
+
+        if ($searchfield->type === 'unknown') {
+            continue;
+        }
         if (!empty($search_array[$field->field->id]->data)) {
             $replacement[] = $searchfield->display_search_field($search_array[$field->field->id]->data);
         } else {
@@ -2450,7 +2476,7 @@ abstract class data_preset_importer {
      * @return bool
      */
     function import($overwritesettings) {
-        global $DB, $CFG;
+        global $DB, $CFG, $OUTPUT;
 
         $params = $this->get_preset_settings();
         $settings = $params->settings;
@@ -2471,7 +2497,7 @@ abstract class data_preset_importer {
                 }
                 else $preservedfields[$cid] = true;
             }
-
+            $missingfieldtypes = [];
             foreach ($newfields as $nid => $newfield) {
                 $cid = optional_param("field_$nid", -1, PARAM_INT);
 
@@ -2488,7 +2514,12 @@ abstract class data_preset_importer {
                     unset($fieldobject);
                 } else {
                     /* Make a new field */
-                    include_once("field/$newfield->type/field.class.php");
+                    $filepath = "field/$newfield->type/field.class.php";
+                    if (!file_exists($filepath)) {
+                        $missingfieldtypes[] = $newfield->name;
+                        continue;
+                    }
+                    include_once($filepath);
 
                     if (!isset($newfield->description)) {
                         $newfield->description = '';
@@ -2499,6 +2530,9 @@ abstract class data_preset_importer {
                     unset($fieldclass);
                 }
             }
+            if (!empty($missingfieldtypes)) {
+                echo $OUTPUT->notification(get_string('missingfieldtypeimport', 'data') . html_writer::alist($missingfieldtypes));
+            }
         }
 
         /* Get rid of all old unused data */
@@ -2954,7 +2988,12 @@ function data_import_csv($cm, $data, &$csvdata, $encoding, $fielddelimiter) {
                     unset($fieldnames[$id]); // To ensure the user provided content fields remain in the array once flipped.
                 } else {
                     $field = $rawfields[$name];
-                    require_once("$CFG->dirroot/mod/data/field/$field->type/field.class.php");
+                    $filepath = "$CFG->dirroot/mod/data/field/$field->type/field.class.php";
+                    if (!file_exists($filepath)) {
+                        $errorfield .= "'$name' ";
+                        continue;
+                    }
+                    require_once($filepath);
                     $classname = 'data_field_' . $field->type;
                     $fields[$name] = new $classname($field, $data, $cm);
                 }
diff --git a/mod/data/locallib.php b/mod/data/locallib.php
index 37cf3e805ec..dad60d6d662 100644
--- a/mod/data/locallib.php
+++ b/mod/data/locallib.php
@@ -270,7 +270,11 @@ class data_portfolio_caller extends portfolio_module_caller_base {
             return true; // too early yet
         }
         foreach ($this->fieldtypes as $key => $field) {
-            require_once($CFG->dirroot . '/mod/data/field/' . $field .'/field.class.php');
+            $filepath = $CFG->dirroot . '/mod/data/field/' . $field .'/field.class.php';
+            if (!file_exists($filepath)) {
+                continue;
+            }
+            require_once($filepath);
             $this->fields[$key] = unserialize(serialize($this->fields[$key]));
         }
     }
@@ -974,7 +978,11 @@ function data_get_tag_title_field($dataid) {
         if ($field->addtemplateposition === false) {
             continue;
         }
-        require_once($CFG->dirroot . '/mod/data/field/' . $field->type . '/field.class.php');
+        $filepath = $CFG->dirroot . '/mod/data/field/' . $field->type . '/field.class.php';
+        if (!file_exists($filepath)) {
+            continue;
+        }
+        require_once($filepath);
         $classname = 'data_field_' . $field->type;
         $field->priority = $classname::get_priority();
         $filteredfields[] = $field;
@@ -1005,11 +1013,19 @@ function data_get_tag_title_field($dataid) {
  *
  * @param stdClass $field The field from the 'data_fields' table
  * @param stdClass $entry The entry from the 'data_records' table
- * @return string The title of the entry
+ * @return string|null It will return the title of the entry or null if the field type is not available.
  */
 function data_get_tag_title_for_entry($field, $entry) {
     global $CFG, $DB;
-    require_once($CFG->dirroot . '/mod/data/field/' . $field->type . '/field.class.php');
+
+    if (!isset($field->type)) {
+        return null;
+    }
+    $filepath = $CFG->dirroot . '/mod/data/field/' . $field->type . '/field.class.php';
+    if (!file_exists($filepath)) {
+        return null;
+    }
+    require_once($filepath);
 
     $classname = 'data_field_' . $field->type;
     $sql = "SELECT dc.*
@@ -1338,7 +1354,7 @@ function data_build_search_array($data, $paging, $searcharray, $defaults = null,
             $searchfield = data_get_field_from_id($field->id, $data);
             // Get field data to build search sql with.  If paging is false, get from user.
             // If paging is true, get data from $searcharray which is obtained from the $SESSION (see line 116).
-            if (!$paging) {
+            if (!$paging && $searchfield->type != 'unknown') {
                 $val = $searchfield->parse_search_field($defaults);
             } else {
                 // Set value from session if there is a value @ the required index.