Index: src/OFString_UTF8.m
==================================================================
--- src/OFString_UTF8.m
+++ src/OFString_UTF8.m
@@ -318,11 +318,11 @@
 				continue;
 			}
 
 			character = table[(uint8_t)cString[i] - 128];
 
-			if (character == 0xFFFD)
+			if (character == 0xFFFF)
 				@throw [OFInvalidEncodingException exception];
 
 			_s->isUTF8 = true;
 			characterBytes = of_string_utf8_encode(character,
 			    buffer);

Index: src/windows_1252.m
==================================================================
--- src/windows_1252.m
+++ src/windows_1252.m
@@ -17,14 +17,14 @@
 #include "config.h"
 
 #import "OFString.h"
 
 const of_char16_t of_windows_1252[128] = {
-	0x20AC, 0xFFFD, 0x201A, 0x0192, 0x201E, 0x2026, 0x2020, 0x2021,
-	0x02C6, 0x2030, 0x0160, 0x2039, 0x0152, 0xFFFD, 0x017D, 0xFFFD,
-	0xFFFD, 0x2018, 0x2019, 0x201C, 0x201D, 0x2022, 0x2013, 0x2014,
-	0x02DC, 0x2122, 0x0161, 0x203A, 0x0153, 0xFFFD, 0x017E, 0x0178,
+	0x20AC, 0xFFFF, 0x201A, 0x0192, 0x201E, 0x2026, 0x2020, 0x2021,
+	0x02C6, 0x2030, 0x0160, 0x2039, 0x0152, 0xFFFF, 0x017D, 0xFFFF,
+	0xFFFF, 0x2018, 0x2019, 0x201C, 0x201D, 0x2022, 0x2013, 0x2014,
+	0x02DC, 0x2122, 0x0161, 0x203A, 0x0153, 0xFFFF, 0x017E, 0x0178,
 	0x00A0, 0x00A1, 0x00A2, 0x00A3, 0x00A4, 0x00A5, 0x00A6, 0x00A7,
 	0x00A8, 0x00A9, 0x00AA, 0x00AB, 0x00AC, 0x00AD, 0x00AE, 0x00AF,
 	0x00B0, 0x00B1, 0x00B2, 0x00B3, 0x00B4, 0x00B5, 0x00B6, 0x00B7,
 	0x00B8, 0x00B9, 0x00BA, 0x00BB, 0x00BC, 0x00BD, 0x00BE, 0x00BF,
 	0x00C0, 0x00C1, 0x00C2, 0x00C3, 0x00C4, 0x00C5, 0x00C6, 0x00C7,