Window Live mail convert email body as attachment

I have installed windows live mail on windows 7 machine.  From last 2 month i am facing problem with emails. while accessing email all of sudden windows live mail convert email body to text attachment.

To read email ,one has to open attachment,this is irritating and time consuming.

I have tried clearing all temp file , reducing email size but nothing is working.Need urgent assistance.

Thanks in Advance

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