jpeg photos are received as wind mail.dat and cannot open

The problem is with how the person has sent them to you - are you able to ask them to send them in plain text or HTML format, and not RTF : http://support.apple.com/kb/TS1506 ?

There are also apps in the app store that say that they can read winmail.dat files (search for 'winmail.dat').

iPhone, iPad, or iPod touch does not display attachment in email

http://support.apple.com/kb/ts1506

Email received from a sender using Outlook includes a Winmail.dat attachment

http://support.microsoft.com/kb/278061

You can use this app. Winmail File Viewer

https://itunes.apple.com/us/app/winmail-file-viewer/id379500151

 Cheers, Tom 😉

And they've tried resending them and they are still coming through as winmail.dat ? Are you able to view them if you access your account Safari ? There are also some free winmail.dat apps which might let you view them e.g. Winmaildat Opener.