I'm using Windows Live and I've received some emails with docx. attachments in which I received the "Prohibited File Type" message.  I've done some searches on the subject and have found that there is a setting in the Windows Live Tools security settings that allow these type of files to be opened.  But by making this change this may expose your computer to a virus contained in an attachment.  What is strange is that I only have this problem on a laptop with Word Starter installed.  I don't have this problem on my desktop with Microsoft Office 2007 installed.  Both computers use Windows Live and have the same antivirus protection and have the same recommended security checks.  The files produced in Word Starter are .docx type yet Windows Live prohibits this type of file to be opened.  To test this I've sent myself emails with files attached produced in the Word Starter program on the laptop.  When the email is received in Windows Live (same computer) the "Prohibited File Type" message occurs.

My questions are;

Why is this happening when the only difference is the version of Word being used?

Is there a safer way to allow these types of files to be opened without removing the security block which Microsoft recommends?

Is there a limitation within Word Starter program that's causing this or does the problem exist with Windows Live?

Thanks