diff --git a/src/ATBAPP/ATBDeviceControllerPlugin.cpp b/src/ATBAPP/ATBDeviceControllerPlugin.cpp
index ec80640..a4a8de2 100644
--- a/src/ATBAPP/ATBDeviceControllerPlugin.cpp
+++ b/src/ATBAPP/ATBDeviceControllerPlugin.cpp
@@ -7,6 +7,7 @@
 
 #include <QPluginLoader>
 #include <QDateTime>
+#include <QFileInfo>
 
 
 ATBDeviceControllerPlugin::ATBDeviceControllerPlugin(QObject *parent) : QObject(parent),
@@ -477,7 +478,26 @@ void ATBDeviceControllerPlugin::onCashPayStoped()
 bool ATBDeviceControllerPlugin::private_loadCashAgentLib(QString pluginName)
 {
     if (pluginName == "") {
-        pluginName = "/usr/lib/libCashAgentLib.so";
+
+        // search list for plugin (.so) file:
+        QStringList pluginNameList;
+        pluginNameList << "/usr/lib/libCAmaster.so"
+                       << "/usr/lib/libCashAgentLib.so";
+        // using C++11 range based loop:
+        for (const auto& filename : pluginNameList) {
+            if (QFileInfo(filename).isReadable()) {
+                pluginName = filename;
+                break;
+            }
+        }
+
+        if (pluginName == "") {
+            qCritical() << "ATBDeviceControllerPlugin: CashAgentLib not installed!";
+            this->errorCode = "CashAgentLib::NOT_FOUND";
+            this->errorDescription = "ERROR: no CashAgentLib: ";
+            return false;
+        }
+
     }
 
     if (!QLibrary::isLibrary(pluginName)) {