diff --git a/lib/fog/aws/models/compute/servers.rb b/lib/fog/aws/models/compute/servers.rb
index fe71ff555..0bdc14f14 100644
--- a/lib/fog/aws/models/compute/servers.rb
+++ b/lib/fog/aws/models/compute/servers.rb
@@ -84,9 +84,14 @@ module Fog
               )
             end
           end
-
-          # make sure port 22 is open in the first security group
+        
           security_group = service.security_groups.get(server.groups.first)
+          if security_group.nil?
+            raise Fog::Compute::AWS::Error, "The security group" \
+              " #{server.groups.first} doesn't exist."
+          end
+          
+          # make sure port 22 is open in the first security group
           authorized = security_group.ip_permissions.detect do |ip_permission|
             ip_permission['ipRanges'].first && ip_permission['ipRanges'].first['cidrIp'] == '0.0.0.0/0' &&
             ip_permission['fromPort'] == 22 &&