update readme

README.md

@@ -7,7 +7,7 @@ The Dashboards reads the tags from the IML appmonitor. You can enable/ disable e
 Author: Axel Hahn; Institute for Medical Education; University of Bern
 
 📄 Source: <https://git-repo.iml.unibe.ch/iml-open-source/appmonitor-dashboard/> \
-📜 License: GNU GPL 3.0 \
+📜 License: GNU GPL 3.0
 
 ## Requirements ##
 
@@ -34,9 +34,12 @@ Open the file `public_html/index.html` in your webbrowser.
 ## Troubleshooting ##
 
 * "no response" error \
-  --> your ip address is not whitelisted in the appmonitor api config.
-* Error 404 \
-  --> no application matches the given tag or tag combination. Delete the tags with button [X] and try to start with a single tag.
+  --> Open the requested api url in the browser. Reasons why does it fail are:
+  * the base url in AM_SERVER_URL does not point to the api url
+  * your ip address is not whitelisted in the appmonitor api config. The api request with the browser identifies a non configured ip as a JSON message.
+  
+* Error 404
+  * no application matches the given tag or tag combination. Delete the tags with button [X] and try to start with a single tag.
 
 ## Screenshot ##