diff --git a/makefile b/makefile
index ab2e7aef7727868d68fc908d8c9ce7bac0a6db75..84f5484b777b362d74e220244bcd90caf05bba72 100644
--- a/makefile
+++ b/makefile
@@ -63,7 +63,7 @@ clean-antlr:
 run-server-screen:
 	@if test "$$(screen -ls | grep -c 'caosdb-screen')" -eq "1"; then \
 		echo "server is probably running. try 'screen -ls'"; \
-		exit 0 ; \
+		exit 1 ; \
 	fi
 	# start and wait for server
 	@screen -L -S caosdb-screen -t server -d -m -A make run
@@ -82,7 +82,7 @@ stop-server-screen:
 run-debug-screen:
 	@if test "$$(screen -ls | grep -c 'caosdb-debug-screen')" -eq "1"; then \
 		echo "server is probably running. try 'screen -ls'"; \
-		exit 0 ; \
+		exit 1 ; \
 	fi
 	# start and wait for server
 	@screen -L -S caosdb-debug-screen -t server -d -m -A make run-debug