diff --git a/fdroidserver/common.py b/fdroidserver/common.py
index e1713d5f..3b524e9e 100644
--- a/fdroidserver/common.py
+++ b/fdroidserver/common.py
@@ -83,7 +83,6 @@ def read_config(opts, config_file='config.py'):
     # Check that commands and binaries do exist
     for key in ('mvn3', 'gradle'):
         if key not in config:
-            print "WARNING: %s not set in config" % key
             continue
         val = config[key]
         executable = find_executable(val)
@@ -94,10 +93,12 @@ def read_config(opts, config_file='config.py'):
     # Check that directories exist
     for key in ('sdk_path', 'ndk_path', 'build_tools'):
         if key not in config:
-            print "WARNING: %s not set in config" % key
             continue
         val = config[key]
         if key == 'build_tools':
+            if 'sdk_path' not in config:
+                print "ERROR: sdk_path needs to be set for build_tools"
+                sys.exit(3)
             val = os.path.join(config['sdk_path'], 'build-tools', val)
         if not os.path.isdir(val):
             print "ERROR: No such directory found for %s: %s" % (key, val)