diff --git a/server.py b/server.py
index 622c4abc47f8e969e5961b9f2eff036fada43731..d3920ac0b7f515050d0ae117b0843f3fefa953e5 100644
--- a/server.py
+++ b/server.py
@@ -423,7 +423,10 @@ def lecture(id):
 		if mode == 'rwth':
 			flash(text+'. <a target="_blank" class="reloadonclose" href="'+url_for('start_rwthauth')+'">Hier authorisieren</a>.')
 		elif mode == 'l2p':
-			flash(text+'. <a target="_blank" class="reloadonclose" href="'+url_for('start_l2pauth')+'">Hier authorisieren</a>.')
+			if 'l2p_courses' in session:
+				flash(text+'. Du bist kein Teilnehmer des L2P-Kurses! <a target="_blank" class="reloadonclose" href="'+url_for('start_l2pauth')+'">Kurse aktualisieren</a>.')
+			else:
+				flash(text+'. <a target="_blank" class="reloadonclose" href="'+url_for('start_l2pauth')+'">Hier authorisieren</a>.')
 		else:
 			flash(text+'.')
 	return render_template('embed.html' if request.endpoint == 'embed' else 'lecture.html', course=courses[0], lecture=lecture, videos=videos, chapters=chapters)