diff --git a/libsrc/leddevice/dev_serial/ProviderRs232.cpp b/libsrc/leddevice/dev_serial/ProviderRs232.cpp
index 295dc491..711a5353 100644
--- a/libsrc/leddevice/dev_serial/ProviderRs232.cpp
+++ b/libsrc/leddevice/dev_serial/ProviderRs232.cpp
@@ -201,7 +201,9 @@ bool ProviderRs232::tryOpen(const int delayAfterConnect_ms)
 	if ( ! _rs232Port.isOpen() )
 	{
 		_frameDropCounter = 0;
-		if (QFile::exists(_deviceName))
+
+		QSerialPortInfo serialPortInfo(_deviceName);
+		if (! serialPortInfo.isNull())
 		{
 			if ( _preOpenDelayTimeOut > QDateTime::currentMSecsSinceEpoch() )
 			{
@@ -223,6 +225,8 @@ bool ProviderRs232::tryOpen(const int delayAfterConnect_ms)
 		}
 		else
 		{
+			QString errortext = QString("Invalid serial device name: [%1]!").arg(_deviceName);
+			this->setInError(errortext);
 			_preOpenDelayTimeOut = QDateTime::currentMSecsSinceEpoch() + _preOpenDelay;
 			return false;
 		}