diff --git a/plugins/database_attachments/database_attachments.php b/plugins/database_attachments/database_attachments.php
index 82c2b59f4..f3804f3c5 100644
--- a/plugins/database_attachments/database_attachments.php
+++ b/plugins/database_attachments/database_attachments.php
@@ -28,7 +28,7 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-if (class_exists('filesystem_attachments', false)) {
+if (class_exists('filesystem_attachments', false) && !defined('TESTS_DIR')) {
     die("Configuration issue. There can be only one enabled plugin for attachments handling");
 }
 
diff --git a/plugins/redundant_attachments/redundant_attachments.php b/plugins/redundant_attachments/redundant_attachments.php
index 2c1246609..55ec3befc 100644
--- a/plugins/redundant_attachments/redundant_attachments.php
+++ b/plugins/redundant_attachments/redundant_attachments.php
@@ -32,7 +32,7 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-if (class_exists('filesystem_attachments', false)) {
+if (class_exists('filesystem_attachments', false) && !defined('TESTS_DIR')) {
     die("Configuration issue. There can be only one enabled plugin for attachments handling");
 }