diff --git a/src/common/common.h b/src/common/common.h
index 22acbdb8..f76b9231 100644
--- a/src/common/common.h
+++ b/src/common/common.h
@@ -91,4 +91,7 @@ DEFINE_GUID(FORT_GUID_FILTER_REAUTH_OUT,
 #define NT_SUCCESS(status)	((LONG) (status) >= 0)
 #endif
 
+#define FORT_STATUS_USER_ERROR	STATUS_INVALID_PARAMETER
+#define FORT_ERROR_USER_ERROR	ERROR_INVALID_PARAMETER
+
 #endif COMMON_H
diff --git a/src/driver/fortcnf.c b/src/driver/fortcnf.c
index 47c1ac17..733e44d0 100644
--- a/src/driver/fortcnf.c
+++ b/src/driver/fortcnf.c
@@ -227,7 +227,7 @@ fort_conf_ref_exe_add_path_locked (PFORT_CONF_REF conf_ref,
     return TRUE;
   } else {
     if (flags.is_new)
-      return STATUS_INVALID_PARAMETER;
+      return FORT_STATUS_USER_ERROR;
 
     // Replace flags
     {
diff --git a/src/driver/fortdrv.c b/src/driver/fortdrv.c
index 23ce6978..295d613c 100644
--- a/src/driver/fortdrv.c
+++ b/src/driver/fortdrv.c
@@ -991,7 +991,7 @@ fort_device_control (PDEVICE_OBJECT device, PIRP irp)
   PIO_STACK_LOCATION irp_stack;
   ULONG_PTR info = 0;
   ULONG control_code;
-  NTSTATUS status = STATUS_INVALID_PARAMETER;
+  NTSTATUS status = STATUS_UNSUCCESSFUL;
 
   irp_stack = IoGetCurrentIrpStackLocation(irp);
   control_code = irp_stack->Parameters.DeviceIoControl.IoControlCode;
@@ -1102,7 +1102,7 @@ fort_device_control (PDEVICE_OBJECT device, PIRP irp)
   default: break;
   }
 
-  if (!NT_SUCCESS(status)) {
+  if (!NT_SUCCESS(status) && status != FORT_STATUS_USER_ERROR) {
     DbgPrintEx(DPFLTR_IHVNETWORK_ID, DPFLTR_ERROR_LEVEL,
                "FORT: Device Control: Error: %x\n", status);
   }
diff --git a/src/driver/fortpkt.c b/src/driver/fortpkt.c
index d8bfb685..fc6fabd6 100644
--- a/src/driver/fortpkt.c
+++ b/src/driver/fortpkt.c
@@ -486,7 +486,7 @@ fort_defer_stream_add (PFORT_DEFER defer,
     if (dataOffset->streamDataOffset != 0
         && (dataOffset->netBuffer != netBuf
         || dataOffset->mdl != NET_BUFFER_CURRENT_MDL(netBuf)))
-      return STATUS_INVALID_PARAMETER;
+      return STATUS_FWP_CANNOT_PEND;
   }
 
   KeAcquireInStackQueuedSpinLock(&defer->lock, &lock_queue);
diff --git a/src/ui/driver/drivermanager.cpp b/src/ui/driver/drivermanager.cpp
index 269ff2fa..53c7912a 100644
--- a/src/ui/driver/drivermanager.cpp
+++ b/src/ui/driver/drivermanager.cpp
@@ -23,24 +23,22 @@ DriverManager::~DriverManager()
     abortWorker();
 }
 
-void DriverManager::setErrorMessage(const QString &errorMessage)
+QString DriverManager::errorMessage() const
 {
-    if (m_errorMessage != errorMessage) {
-        m_errorMessage = errorMessage;
-        emit errorMessageChanged();
-    }
+    return (m_errorCode == 0) ? QString()
+                              : OsUtil::errorMessage(m_errorCode);
 }
 
 void DriverManager::updateError(bool success)
 {
     m_errorCode = success ? 0 : OsUtil::lastErrorCode();
-    setErrorMessage(success ? QString()
-                            : OsUtil::lastErrorMessage(m_errorCode));
+    emit errorMessageChanged();
 }
 
 bool DriverManager::isDeviceError() const
 {
-    return m_errorCode == OsUtil::userErrorCode();
+    return m_errorCode != 0
+            && m_errorCode != FortCommon::userErrorCode();
 }
 
 void DriverManager::setupWorker()
diff --git a/src/ui/driver/drivermanager.h b/src/ui/driver/drivermanager.h
index bda337a6..7239e4e0 100644
--- a/src/ui/driver/drivermanager.h
+++ b/src/ui/driver/drivermanager.h
@@ -22,7 +22,7 @@ public:
 
     DriverWorker *driverWorker() const { return m_driverWorker; }
 
-    QString errorMessage() const { return m_errorMessage; }
+    QString errorMessage() const;
     bool isDeviceError() const;
 
     bool isDeviceOpened() const;
@@ -59,8 +59,6 @@ private:
 
     Device *m_device = nullptr;
     DriverWorker *m_driverWorker = nullptr;
-
-    QString m_errorMessage;
 };
 
 #endif // DRIVERMANAGER_H
diff --git a/src/ui/driver/driverworker.cpp b/src/ui/driver/driverworker.cpp
index a2c2a346..dd779bfb 100644
--- a/src/ui/driver/driverworker.cpp
+++ b/src/ui/driver/driverworker.cpp
@@ -109,7 +109,7 @@ void DriverWorker::readLog()
     if (success) {
         m_logBuffer->reset(nr);
     } else if (!m_cancelled) {
-        errorMessage = OsUtil::lastErrorMessage();
+        errorMessage = OsUtil::errorMessage();
     }
 
     emitReadLogResult(success, errorMessage);
diff --git a/src/ui/form/opt/pages/optionspage.cpp b/src/ui/form/opt/pages/optionspage.cpp
index c89a4ea2..694fe19b 100644
--- a/src/ui/form/opt/pages/optionspage.cpp
+++ b/src/ui/form/opt/pages/optionspage.cpp
@@ -310,13 +310,12 @@ void OptionsPage::setupDriverIcon()
                 : ":/images/plugin_disabled.png";
 
         m_iconDriver->setPixmap(QPixmap(iconPath));
-
-        retranslateDriverMessage();
     };
 
     refreshDriverIcon();
 
     connect(driverManager(), &DriverManager::isDeviceOpenedChanged, this, refreshDriverIcon);
+    connect(driverManager(), &DriverManager::errorMessageChanged, this, &OptionsPage::retranslateDriverMessage);
 }
 
 void OptionsPage::setupNewVersionBox()
diff --git a/src/ui/fortcommon.cpp b/src/ui/fortcommon.cpp
index ea7fc28d..df9b42da 100644
--- a/src/ui/fortcommon.cpp
+++ b/src/ui/fortcommon.cpp
@@ -53,6 +53,11 @@ quint32 FortCommon::ioctlDelApp()
     return FORT_IOCTL_DELAPP;
 }
 
+quint32 FortCommon::userErrorCode()
+{
+    return FORT_ERROR_USER_ERROR;
+}
+
 int FortCommon::bufferSize()
 {
     return FORT_BUFFER_SIZE;
diff --git a/src/ui/fortcommon.h b/src/ui/fortcommon.h
index 97ecc132..e67b9eef 100644
--- a/src/ui/fortcommon.h
+++ b/src/ui/fortcommon.h
@@ -20,6 +20,8 @@ public:
     static quint32 ioctlAddApp();
     static quint32 ioctlDelApp();
 
+    static quint32 userErrorCode();
+
     static int bufferSize();
 
     static quint32 confIoConfOff();
diff --git a/src/ui/util/osutil.cpp b/src/ui/util/osutil.cpp
index 1f65c7bd..e8e37dc7 100644
--- a/src/ui/util/osutil.cpp
+++ b/src/ui/util/osutil.cpp
@@ -28,17 +28,12 @@ bool OsUtil::createGlobalMutex(const char *name)
             && GetLastError() != ERROR_ALREADY_EXISTS;
 }
 
-quint32 OsUtil::userErrorCode()
-{
-    return STATUS_INVALID_PARAMETER;
-}
-
 quint32 OsUtil::lastErrorCode()
 {
     return GetLastError();
 }
 
-QString OsUtil::lastErrorMessage(quint32 errorCode)
+QString OsUtil::errorMessage(quint32 errorCode)
 {
     LPWSTR buf = nullptr;
 
diff --git a/src/ui/util/osutil.h b/src/ui/util/osutil.h
index 2065375f..9d67f54b 100644
--- a/src/ui/util/osutil.h
+++ b/src/ui/util/osutil.h
@@ -14,9 +14,8 @@ public:
 
     static bool createGlobalMutex(const char *name);
 
-    static quint32 userErrorCode();
     static quint32 lastErrorCode();
-    static QString lastErrorMessage(quint32 errorCode = lastErrorCode());
+    static QString errorMessage(quint32 errorCode = lastErrorCode());
 
     static qint32 getTickCount();
 };