diff --git a/admin/tool/behat/tests/behat/data_generators.feature b/admin/tool/behat/tests/behat/data_generators.feature
index 3617ccc975e..9423a39d6d6 100644
--- a/admin/tool/behat/tests/behat/data_generators.feature
+++ b/admin/tool/behat/tests/behat/data_generators.feature
@@ -156,7 +156,7 @@ Feature: Set up contextual data for tests
     And I log in as "user5"
     And I should see "You are logged in as"
     And I am on "Course 1" course homepage
-    And I should see "You can not enrol yourself in this course."
+    And I should see "You cannot enrol yourself in this course."
 
   Scenario: Add modules
     Given the following "courses" exist:
diff --git a/course/tests/behat/course_browsing.feature b/course/tests/behat/course_browsing.feature
index 8fefc5b1265..4993d076e20 100644
--- a/course/tests/behat/course_browsing.feature
+++ b/course/tests/behat/course_browsing.feature
@@ -79,7 +79,7 @@ Feature: Restricting access to course lists
     And I should not see "Humanities"
     And I should not see "Other category"
     And I follow "English Y2"
-    And I should see "You can not enrol yourself in this course."
+    And I should see "You cannot enrol yourself in this course."
     And I log out
 
   Scenario: Browse courses as a user who has access to several but not all categories
@@ -102,5 +102,5 @@ Feature: Restricting access to course lists
     And the "Course categories" select box should contain "English category"
     And the "Course categories" select box should not contain "Other category"
     And I follow "Biology Y1"
-    And I should see "You can not enrol yourself in this course."
+    And I should see "You cannot enrol yourself in this course."
     And I log out
diff --git a/enrol/self/tests/behat/self_enrolment.feature b/enrol/self/tests/behat/self_enrolment.feature
index 35ddfce7275..91551f027a2 100644
--- a/enrol/self/tests/behat/self_enrolment.feature
+++ b/enrol/self/tests/behat/self_enrolment.feature
@@ -62,7 +62,7 @@ Feature: Users can auto-enrol themself in courses where self enrolment is allowe
   Scenario: Self-enrolment disabled
     Given I log in as "student1"
     When I am on "Course 1" course homepage
-    Then I should see "You can not enrol yourself in this course"
+    Then I should see "You cannot enrol yourself in this course"
 
   Scenario: Self-enrolment enabled requiring a group enrolment key
     Given I log in as "teacher1"
diff --git a/lib/filestorage/file_exceptions.php b/lib/filestorage/file_exceptions.php
index 61304f80a6d..7639810933f 100644
--- a/lib/filestorage/file_exceptions.php
+++ b/lib/filestorage/file_exceptions.php
@@ -46,7 +46,7 @@ class file_exception extends moodle_exception {
 }
 
 /**
- * Can not create file exception.
+ * Cannot create file exception.
  *
  * @package   core_files
  * @category  files
diff --git a/lib/filestorage/tests/file_storage_test.php b/lib/filestorage/tests/file_storage_test.php
index 62c19f30e13..3134458af96 100644
--- a/lib/filestorage/tests/file_storage_test.php
+++ b/lib/filestorage/tests/file_storage_test.php
@@ -324,7 +324,7 @@ class core_files_file_storage_testcase extends advanced_testcase {
 
         // Try break it.
         $this->expectException('file_exception');
-        $this->expectExceptionMessage('Can not create file "1/core/unittest/0/test/newtest.txt" (file exists, cannot rename)');
+        $this->expectExceptionMessage('Cannot create file 1/core/unittest/0/test/newtest.txt (file exists, cannot rename)');
         // This shall throw exception.
         $originalfile->rename($newpath, $newname);
     }
@@ -1478,7 +1478,7 @@ class core_files_file_storage_testcase extends advanced_testcase {
 
         // Creating a file validating unique constraint.
         $this->expectException(stored_file_creation_exception::class);
-        $this->expectExceptionMessage('Can not create file "1/core/phpunit/0/testfile.txt"');
+        $this->expectExceptionMessage('Cannot create file 1/core/phpunit/0/testfile.txt');
         $fs->create_file_from_storedfile($filerecord, $file1->get_id());
     }
 
@@ -1835,7 +1835,7 @@ class core_files_file_storage_testcase extends advanced_testcase {
 
         // Creating a file validating unique constraint.
         $this->expectException(stored_file_creation_exception::class);
-        $this->expectExceptionMessage('Can not create file "1/core/phpunit/0/testfile.txt"');
+        $this->expectExceptionMessage('Cannot create file 1/core/phpunit/0/testfile.txt');
         $file2 = $fs->create_file_from_pathname($filerecord, $path);
     }
 
diff --git a/lib/filestorage/tests/file_system_filedir_test.php b/lib/filestorage/tests/file_system_filedir_test.php
index 3896770cc59..bc6c7846a9a 100644
--- a/lib/filestorage/tests/file_system_filedir_test.php
+++ b/lib/filestorage/tests/file_system_filedir_test.php
@@ -154,7 +154,7 @@ class core_files_file_system_filedir_testcase extends advanced_testcase {
         // This should generate an exception.
         $this->expectException('file_exception');
         $this->expectExceptionMessageMatches(
-            '/Can not create local file pool directories, please verify permissions in dataroot./');
+            '/Cannot create local file pool directories. Please verify permissions in dataroot./');
 
         new file_system_filedir();
     }
@@ -178,7 +178,7 @@ class core_files_file_system_filedir_testcase extends advanced_testcase {
         // This should generate an exception.
         $this->expectException('file_exception');
         $this->expectExceptionMessageMatches(
-            '/Can not create local file pool directories, please verify permissions in dataroot./');
+            '/Cannot create local file pool directories. Please verify permissions in dataroot./');
 
         new file_system_filedir();
     }
@@ -835,7 +835,7 @@ class core_files_file_system_filedir_testcase extends advanced_testcase {
 
         $this->expectException('file_exception');
         $this->expectExceptionMessageMatches(
-            "/Can not create local file pool directories, please verify permissions in dataroot./");
+            "/Cannot create local file pool directories. Please verify permissions in dataroot./");
 
         // Attempt to add the file to the file pool.
         $fs = new file_system_filedir();
@@ -893,7 +893,7 @@ class core_files_file_system_filedir_testcase extends advanced_testcase {
 
         $this->expectException('file_exception');
         $this->expectExceptionMessageMatches(
-            "/Can not create local file pool directories, please verify permissions in dataroot./");
+            "/Cannot create local file pool directories. Please verify permissions in dataroot./");
 
         // Attempt to add the file to the file pool.
         $fs = new file_system_filedir();