email attachments

I cannot always open an attachment in an email.  The attachments are on Word or Excel, both supported by my computer.  I  have closed the Windows Live Mail and then re-opened it, with no change.

First I left-click twice on the attachment. When nothing happens, I try right-clicking, click on open.  Nothing happens.  Then I right-click on 'Copy' but cannot copy to Word.  I also tried 'Save-as' but could not find the document.

Sometimes the attachment will open and sometimes it will not.