diff -r ed0e5edd443d src/org/openbravo/erpCommon/obps/ActivationKey.java
--- a/src/org/openbravo/erpCommon/obps/ActivationKey.java	Mon Dec 10 18:31:33 2018 +0100
+++ b/src/org/openbravo/erpCommon/obps/ActivationKey.java	Thu Jun 20 13:36:51 2019 +0200
@@ -830,7 +830,8 @@
     }
 
     // maxUsers==0 is unlimited concurrent users
-    boolean checkConcurrentUsers = maxUsers != 0 && consumesConcurrentUser(sessionType);
+    boolean checkConcurrentUsers = maxUsers != 0 && currentSession != null
+        && consumesConcurrentUser(sessionType);
     if (checkConcurrentUsers) {
       OBContext.setAdminMode();
       int activeSessions = 0;