Attachment viewing in Windows 7.5 phone

Attachment viewing in Windows 7.5 phone

Hi,
 
This is just to inform you that attachments (Word, Excel, PowerPoint, PDF) sent via Zoho Mail do not appear and cannot be downloaded when sent to a Windows phone when I send as Rich Text with my signature.  If I send as plain text the Windows Phone can see the attachments. The same email and attachments can be viewed and downloaded from desktops, Mac and iPhone.
 
Thanks!