Updated Debugging (markdown)

Debugging-&-FAW.md

@@ -1,6 +1,17 @@
+## FAQ
+
+### Missing or wrong application key
+
+**Error**: `https://github.com/invoiceninja/dockerfiles/wiki/prerequisites#generate-an-application-key`
+
+**Solution**  
+You did not properly insert a valid application key. Please [check here](https://github.com/invoiceninja/dockerfiles/wiki/prerequisites#generate-an-application-key) and the linked blog post.
+
+
+## Debugging 
 Even when running your Invoice Ninja setup with Docker - errors can occur. Depending on where the error happens - the webserver, Invoice Ninja or the database - different log files can be responsible. 
 
-## Show logs without `docker-compose`
+### Show logs without `docker-compose`
 
 If you are not running `docker-compose` you first need to find the container id for your php container with `docker ps`. Then you can run
 
@@ -10,7 +21,7 @@ docker logs -f <CONTAINER NAME>
 
 This gives you a constant output of the log files for the php container.
 
-## Show logs with `docker-compose`
+### Show logs with `docker-compose`
 
 If you are running the `docker-compose` setup you can output all logs, from all containers, with the following command