diff --git a/php/src/Docker/DockerActionManager.php b/php/src/Docker/DockerActionManager.php
index 0d203bda..812d93ca 100644
--- a/php/src/Docker/DockerActionManager.php
+++ b/php/src/Docker/DockerActionManager.php
@@ -431,6 +431,10 @@ class DockerActionManager
             $tagArray = explode(':', $output['Config']['Image']);
             $tag = $tagArray[1];
             apcu_add($cacheKey, $tag);
+            if ($tag === null) {
+                error_log("No tag was found when getting the current channel. You probably did not follow the documentation correctly. Changing the channel to the default 'latest'.");
+                $tag = 'latest';
+            }
             return $tag;
         } catch (\Exception $e) {
             error_log('Could not get current channel ' . $e->getMessage());