Place said some of the furor is possibly being fueled by spammers who want to be better able to reach Verizon users. Two of the complaints the company received, Place said, came from individuals known to be spammers.
Those explanations are met with a dubious eye by some technical experts.
"Every ISP is desperate to do something about spam," said John R. Levine, who until recently headed a working group developing technical standards for technology to combat spam. By some estimates, spam accounts for more than 70 percent of all e-mail traversing electronic networks, and spammers are adroit in evading barriers thrown up by users and Internet service providers.
But Verizon, Levine said, has been known for anti-spam efforts that were "fabulously not thought through."
Levine, who is not a Verizon customer but has talked to many others who are, said he suspects Verizon decided to block mail from all ISPs in certain areas, and then let legitimate ones back on the approved list after they complained.
At the very least, Levine said, Verizon should be more forthright with its customers.
Sher agrees.
"They addressed a real problem by taking a sledgehammer rather than a scalpel," he said. "And they have too much invested in their system to change it."
