diff --git a/src/common/filesystem/source/unicode.cpp b/src/common/filesystem/source/unicode.cpp
index d102f1fc05..7b5fd2aefb 100644
--- a/src/common/filesystem/source/unicode.cpp
+++ b/src/common/filesystem/source/unicode.cpp
@@ -121,7 +121,7 @@ void ibm437_to_utf8(const char* in, std::vector<char>& buffer)
 
 	while (int char1 = (uint8_t)*in++)
 	{
-		if (char1 >= 0x80) char1 = ibm437map[char1];
+		if (char1 >= 0x80) char1 = ibm437map[char1 - 0x80];
 		utf8_encode(char1, buffer);
 	}
 	buffer.push_back(0);
@@ -140,4 +140,22 @@ char *tolower_normalize(const char *str)
 	return (char*)retval;
 }
 
+//==========================================================================
+//
+// validates the string for proper UTF-8
+//
+//==========================================================================
+
+bool unicode_validate(const char* str)
+{
+	while (*str != 0)
+	{
+		int cp;
+		int result = utf8proc_iterate((const uint8_t*)str, -1, &cp);
+		if (result < 0) return false;
+	}
+	return true;
+}
+
+
 }
diff --git a/src/common/filesystem/source/unicode.h b/src/common/filesystem/source/unicode.h
index 6df51668d1..8783dbc718 100644
--- a/src/common/filesystem/source/unicode.h
+++ b/src/common/filesystem/source/unicode.h
@@ -6,7 +6,7 @@ namespace FileSys {
 	
 void utf16_to_utf8(const unsigned short* in, std::vector<char>& buffer);
 void ibm437_to_utf8(const char* in, std::vector<char>& buffer);
-int unicode_tolower(int c);
 char *tolower_normalize(const char *str);
+bool unicode_validate(const char* str);
 
 }