diff --git a/PowerEditor/src/NppIO.cpp b/PowerEditor/src/NppIO.cpp
index aacba39d..d2121395 100644
--- a/PowerEditor/src/NppIO.cpp
+++ b/PowerEditor/src/NppIO.cpp
@@ -31,6 +31,7 @@
 #include "FileDialog.h"
 #include "EncodingMapper.h"
 #include "VerticalFileSwitcher.h"
+#include <TCHAR.h>
 
 
 BufferID Notepad_plus::doOpen(const TCHAR *fileName, bool isReadOnly, int encoding)
@@ -289,7 +290,8 @@ bool Notepad_plus::doSave(BufferID id, const TCHAR * filename, bool isCopy)
 		_pluginsManager.notify(&scnN);
 	}
 
-	bool res = MainFileManager->saveBuffer(id, filename, isCopy);
+	generic_string error_msg;
+	bool res = MainFileManager->saveBuffer(id, filename, isCopy, &error_msg);
 
 	if (!isCopy)
 	{
@@ -298,11 +300,20 @@ bool Notepad_plus::doSave(BufferID id, const TCHAR * filename, bool isCopy)
 	}
 
 	if (!res)
-		_nativeLangSpeaker.messageBox("FileLockedWarning",
-		_pPublicInterface->getHSelf(),
-		TEXT("Please check if this file is opened in another program."),
-		TEXT("Save failed"), 
-		MB_OK);
+	{
+		if(error_msg.empty())
+		{
+			_nativeLangSpeaker.messageBox("FileLockedWarning",
+			_pPublicInterface->getHSelf(),
+			TEXT("Please check if this file is opened in another program."),
+			TEXT("Save failed"), 
+			MB_OK);
+		}
+		else
+		{
+			::MessageBox(_pPublicInterface->getHSelf(), error_msg.c_str(), TEXT("Save failed"), MB_OK);
+		}
+	}
 	return res;
 }
 
diff --git a/PowerEditor/src/ScitillaComponent/Buffer.cpp b/PowerEditor/src/ScitillaComponent/Buffer.cpp
index b0c4c990..db58e20d 100644
--- a/PowerEditor/src/ScitillaComponent/Buffer.cpp
+++ b/PowerEditor/src/ScitillaComponent/Buffer.cpp
@@ -595,7 +595,7 @@ bool FileManager::moveFile(BufferID id, const TCHAR * newFileName)
 	return true;
 }
 
-bool FileManager::saveBuffer(BufferID id, const TCHAR * filename, bool isCopy) {
+bool FileManager::saveBuffer(BufferID id, const TCHAR * filename, bool isCopy, generic_string * error_msg) {
 	Buffer * buffer = getBufferByID(id);
 	bool isHidden = false;
 	bool isSys = false;
@@ -636,9 +636,10 @@ bool FileManager::saveBuffer(BufferID id, const TCHAR * filename, bool isCopy) {
 
 		int lengthDoc = _pscratchTilla->getCurrentDocLen();
 		char* buf = (char*)_pscratchTilla->execute(SCI_GETCHARACTERPOINTER);	//to get characters directly from Scintilla buffer
+		size_t items_written = 0;
 		if (encoding == -1) //no special encoding; can be handled directly by Utf8_16_Write
 		{
-			UnicodeConvertor.fwrite(buf, lengthDoc);
+			items_written = UnicodeConvertor.fwrite(buf, lengthDoc);
 		}
 		else
 		{
@@ -654,11 +655,20 @@ bool FileManager::saveBuffer(BufferID id, const TCHAR * filename, bool isCopy) {
 				int incompleteMultibyteChar = 0;
 				const char *newData = wmc->encode(SC_CP_UTF8, encoding, buf+i, grabSize, &newDataLen, &incompleteMultibyteChar);
 				grabSize -= incompleteMultibyteChar;
-				UnicodeConvertor.fwrite(newData, newDataLen);
+				items_written = UnicodeConvertor.fwrite(newData, newDataLen);
 			}
 		}
 		UnicodeConvertor.fclose();
 
+		// Error, we didn't write the entire document to disk.
+		// Note that fwrite() doesn't return the number of bytes written, but rather the number of ITEMS.
+		if(items_written != 1)
+		{
+			if(error_msg != NULL)
+				*error_msg = TEXT("Not enough space on disk to save file.");
+			return false;
+		}
+
 		if (isHidden)
 			::SetFileAttributes(fullpath, attrib | FILE_ATTRIBUTE_HIDDEN);
 
diff --git a/PowerEditor/src/ScitillaComponent/Buffer.h b/PowerEditor/src/ScitillaComponent/Buffer.h
index 730ac67f..06c2a67b 100644
--- a/PowerEditor/src/ScitillaComponent/Buffer.h
+++ b/PowerEditor/src/ScitillaComponent/Buffer.h
@@ -101,7 +101,7 @@ public:
 
 	bool reloadBuffer(BufferID id);
 	bool reloadBufferDeferred(BufferID id);
-	bool saveBuffer(BufferID id, const TCHAR * filename, bool isCopy = false);
+	bool saveBuffer(BufferID id, const TCHAR * filename, bool isCopy = false, generic_string * error_msg = NULL);
 	bool deleteFile(BufferID id);
 	bool moveFile(BufferID id, const TCHAR * newFilename);