diff --git a/UI/MailPartViewers/UIxMailPartHTMLViewer.m b/UI/MailPartViewers/UIxMailPartHTMLViewer.m
index e0cdb6193..7250c5ebe 100644
--- a/UI/MailPartViewers/UIxMailPartHTMLViewer.m
+++ b/UI/MailPartViewers/UIxMailPartHTMLViewer.m
@@ -84,6 +84,7 @@ _xmlCharsetForCharset (NSString *charset)
     { @"koi8-r", XML_CHAR_ENCODING_ERROR},       // unsupported, will trigger koi8-r -> utf8 conversion
     { @"windows-1250", XML_CHAR_ENCODING_ERROR}, // unsupported, will trigger windows-1250 -> utf8 conversion
     { @"windows-1251", XML_CHAR_ENCODING_ERROR}, // unsupported, will trigger windows-1251 -> utf8 conversion
+    { @"windows-1255", XML_CHAR_ENCODING_ERROR}, // unsupported, will trigger windows-1251 -> utf8 conversion
     { @"windows-1257", XML_CHAR_ENCODING_ERROR}, // unsupported, will trigger windows-1257 -> utf8 conversion
     { @"gb2312", XML_CHAR_ENCODING_ERROR},       // unsupported, will trigger gb2312 -> utf8 conversion
     { @"gbk", XML_CHAR_ENCODING_ERROR},          // unsupported, will trigger gb2312 -> utf8 conversion