Windows 7 - Attachment security alert Outlook 2003

I need help.

Let me explain step by step:

1 - I used XP, Outlook2003 and Irphan View without any problem.

2- I start to use Windows7 and Outlook2003. The annoyng alerts began to appear to any attachmentes except JPEG that were opened with the MS Image Vier.

3- I installed Irphan View and the alerts now include JPEG files also.

So the problem is in the Windows 7 and not in Outllok or Irphan View.

I was told that this issue began with Vista(I didn't try it) and remains in Windows 7.


I really don't know how to stop this and any help will be very appreciated.