Anchor links are not universally supported by all email clients and receiving mail servers. Some email providers do not support them at all while others support them minimally or inconsistently. For best results, test the message you intend to send using the broadest number of mail clients that you have available (Outlook, Gmail, Yahoo, AOL, etc.) to test this and all functionality. You may also choose to not use anchor links in emails due to their varied support by email clients.

Traditional anchors use the format: 
<a id="anchorname"></a>   

Replace this with:
<a name="anchorname"></a>