Update June 28:
My computer system crashed so badly that my initial attempts at reinstallation failed several times. It went into a loop repeatedly instead of opening Windows. Fortunately, this morning's attempt was successful. My Yahoo email account had been compromised and spamming emails sent to those in my addressbook. My apologies to those who have received them. Among the viruses and trojan horses was one described as 'dllhost.exe is infected with Dialer:win32/Egroupsexdial' which can be embarrassing to me.
Please be informed that the rascal Edmund Palumbo (whoever he is) had given me too much credit for trying to steal his password. I wish I know how to! It was his accusation which led me to opening the attachment out of curiosity. Let this be a lesson to those using the internet.