WASHINGTON — A year after the U.S. Congress passed the first federal antispam law, observers see no evidence that it has cut the amount of unwanted commercial e-mail arriving in people’s in-boxes.

A year after the U.S. Congress passed the first federal antispam law, observers see no evidence that it has cut the amount of unwanted commercial e-mail arriving in U.S. residents’ inboxes. Most ...

or some, spam is like ants at a picnic: uninvited, ubiquitous and annoying. For many others, whose uninvited e-mails flood their computer mailbox, it’s an expensive headache. Try as you might, ...