diff -r 0e8ae154aed5 src/org/openbravo/retail/posterminal/ProcessCashMgmt.java
--- a/src/org/openbravo/retail/posterminal/ProcessCashMgmt.java	Wed Aug 17 15:39:04 2016 -0600
+++ b/src/org/openbravo/retail/posterminal/ProcessCashMgmt.java	Mon Aug 22 16:29:03 2016 +0200
@@ -16,6 +16,7 @@
 import org.apache.log4j.Logger;
 import org.codehaus.jettison.json.JSONObject;
 import org.openbravo.advpaymentmngt.dao.TransactionsDao;
+import org.openbravo.base.exception.OBException;
 import org.openbravo.base.provider.OBProvider;
 import org.openbravo.dal.core.OBContext;
 import org.openbravo.dal.service.OBDal;
@@ -52,6 +53,9 @@
     String cashManagementReasonId = jsonsent.getString("reasonId");
     String cashupId = jsonsent.getString("cashup_id");
     OBPOSAppCashup cashup = OBDal.getInstance().get(OBPOSAppCashup.class, cashupId);
+    if (cashup == null) {
+      throw new OBException("The cashup with ID '" + jsonsent.getString("cashup_id") + "' does not exists in the system. Please synchronize it first and then process this entry.");
+    }
     TerminalTypePaymentMethod terminalPaymentMethod = paymentMethod.getPaymentMethod();
     GLItem glItemMain;
     GLItem glItemSecondary;