[arch-general] The principle behind MSN & Yahoo invisible scanners?

[Mauro Santos]

Mind you that since some time ago it seems this "feature" is not
reliable anymore.

The are msn clients that had this functionality built-in and things have
gone south when it started to malfunction and reporting some users as
being blocked or deleted when in fact they are not.

As far as I know no one knows for sure what the problem was (maybe just
a change in protocol or a deliberate change). I have tested it myself
with several different accounts and it was similar to a russian
roulette, this "feature" was not reliable anymore in identifying when
one has been blocked/deleted.

Search more about this in mercury's forums, at least the problem came up
there and also on amsn's forums if I remember correctly.

-- 
Mauro Santos