Live Mail 2012 content of some mails invisible

Some of the emails I receive in Windows Live Mail 2012 on a Windows 7 64-bits seem to be completely empty.
I can reproduce the problem with a fresh installation of Live Mail 2012 on a Windows 8 32-bits system

I noted:

• When I print the mail, only the header is printed, no content
• The mail content is visible at  gmail.com and in clients Live Mail 2009 (XP), outlook 2013 and  windows phone
• When I click on reply all text and pictures become visible
• So far I have only had this problem with mail from 1 sender, but not all mail from that sender is affected.
  In fact it only occurs with automated replies from that sender. The sender has not seen this problem before.
  
• I use Windows 7 with standard firewall and Security Essentials. Windows is fully patched, 64 bits
• I have tried to solve this by using the repair function in control panel and by compressing the database though the problem occurs also with a fresh installation on W8.

What could be wrong?