message requiring me to "confirm" my email account -- is it from AVAST?

another symptom of malware ???:
my hotmail email account (but not my son’s – his is still normal) will not let me send email messages. When I try I get this:

(a yellow triangle with an exclamation mark in it) “Before you can send this message, you must pass a random check to confirm that your account is valid. This helps us prevent automated programs from sending junk e-mail.”
(then in blue) “confirm your email account.”

this began right after the malware incident described in “malware – unable to scan – error occured during moving file and file deleting.” I haven’t clicked on that blue invitation.

Does this message come from AVAST? Or is it someone trying to find my email password?

thanks.

Please, do not post twice. Just double the help effort.
http://forum.avast.com/index.php?topic=33902.msg283620#msg283620