Yesterday's story showing evidence that Microsoft has placed Draconian caps on the number of Hotmail recipients who can receive an email prompted a message from reader Jeff Willis. He says Hotmail routinely blocks mass emails his company, MIS Sciences Corporation, sends on behalf of universities and government agencies.
That's a problem, and it would seem to us, a potential liability for Microsoft, because the blocked dispatches occasionally relate to emergencies, such as when a transit agency notifies subscribers that current weather conditions have rendered a particular traffic route unsafe.
"What's going to happen is an emergency message is going to go out and they're not going to get the message," says Willis, who envisions a handicapped driver getting stuck on a washed-out stretch of highway shortly after Hotmail blocked a warning about a flash flood. "Somebody's going to get hurt."
For the past three months or so, every dispatch sent by MIS results in a flood of rejection notices from Hotmail that read: "452 Too many recipients received this hour." If his list includes 100 Hotmail addressees, Willis will receive 90 failure notices, leading him to surmise that Microsoft lets in 10 and rejects the remainder for a set period of time.
MIS imposes a double opt-in policy for every email list it maintains, meaning users must first visit a website to request their name be added and then they must respond to an email sent to the address they gave. The company connects directly to the Qwest backbone, has SPF, domain keys and proper DNS pointers.
Willis's story comes as Hotmail, Yahoo Mail and other large email providers struggle to cope with the growing amount of spam and other email-borne crud that floods their servers daily. Hotmail alone receives 4.5 billion fraudulent emails per day, an official said a few months ago.
But while the spam problem is global, Hotmail is the only provider that blocks the the alerts, Willis says. He has been in regular contact with Hotmail support people, who have been unable to fix the problem.
A Microsoft statement said in most cases Hotmail will deliver a given email to 100 recipients within a short timeframe.
"But, for IPs that are categorized as unknown or known to be bad, Microsoft limits this number below the recommended default, limiting the spam and abuse to the system. For IPs that hit their max recipients limit we return "552 too many recipients." Microsoft is committed to investing in sender classification and will be limiting the False Positives for users, as well improving their escalation experience."
The statement didn't explain how Willis's outfit could reasonably be categorized as "unknown or known to be bad." ®