system 10.9.4 + Mail 7.3 not showing images in email

My Macbook Pro 17 is running 10.9.4 and mail 7.3. Has been running well until mail stopped loading some images in emails. My emails from the normal people i get them from now show blue boxes with ? marks symbols in them. Can anyone suggest a fix.

First thing to check: how do the same emails look when you visit your webmail portal through a browser?

Is it possible you have recently run any utilities lately? If so, which ones?

Thanks for the reply - i have run disk utilities and repaired any permissions (did not see any relating to mail)
Also the emails view fine on my other macs, when i check them on the laptop the images included dont show. I am running exchange imap account that syncs across my macs and phone. All other are fine.
If i click on the boxes they open in safari and show up fine. I have checked mail preferences under viewing and display html images is checked. I am new to the forums and have done a screen grab of how the email looks but dont know how to post it ?