diff --git a/PowerEditor/src/Notepad_plus.cpp b/PowerEditor/src/Notepad_plus.cpp
index 13e97d09..aba7b488 100644
--- a/PowerEditor/src/Notepad_plus.cpp
+++ b/PowerEditor/src/Notepad_plus.cpp
@@ -5835,13 +5835,21 @@ DWORD WINAPI Notepad_plus::backupDocument(void * /*param*/)
 	bool isSnapshotMode = true;
 	while (isSnapshotMode)
 	{
-		size_t timer = NppParameters::getInstance()->getNppGUI()._snapshotBackupTiming;
+		NppParameters *nppParam = NppParameters::getInstance();
+		if (!nppParam)
+			return FALSE;
+
+		size_t timer = nppParam->getNppGUI()._snapshotBackupTiming;
 		if (timer < 1000)
 			timer = 1000;
 
 		::Sleep(timer);
 
-		isSnapshotMode = NppParameters::getInstance()->getNppGUI().isSnapshotMode();
+		nppParam = NppParameters::getInstance();
+		if (!nppParam)
+			return FALSE;
+
+		isSnapshotMode = nppParam->getNppGUI().isSnapshotMode();
 		if (!isSnapshotMode)
 			break;
 
diff --git a/PowerEditor/src/Parameters.cpp b/PowerEditor/src/Parameters.cpp
index dce97bef..5a07a6a6 100644
--- a/PowerEditor/src/Parameters.cpp
+++ b/PowerEditor/src/Parameters.cpp
@@ -1562,6 +1562,7 @@ void NppParameters::destroyInstance()
 		delete _pXmlBlacklistDoc;
 
 	delete _pSelf;
+	_pSelf = NULL;
 }
 
 void NppParameters::setFontList(HWND hWnd)