Old home computer that probably needs ditching! Running Win 7

Windows live Mail is the current Email program, been on it for many years.

Problem is it will not allow a 'reply' . It puts a message in a rectangular box  - "Windows is having trouble opening this message. Try again later"   

Of course 'later brings the same result.

Should I ditch Windows Live mail?  or delete the program and re-load it?

TIA