Speaker-maker Sonos has apologized after accidentally revealing the email addresses of hundreds of its customers to each other.
The firm upset people last week by saying it will stop issuing software updates for its older devices from May.
A staff member was emailing customers who had complained about the decision.
But instead of using the blind copy field, they used the regular copy all one, which meant that recipients could see each other’s email addresses.
In a statement to the BBC, Sonos said: “Earlier today, an email was sent in response to a number of customer inquiries that included email addresses. No further information was included.
“We have apologised to each customer affected by this error and have put in place processes to ensure this will not happen again.”
The blanket email was sent to more than 450 people. It apologised for a delayed response and noted that Sonos had received an “unprecedented number of emails” in recent days.
Some users who received the email took to Twitter to express their anger.
“Hi @sonos, thanks for sharing my email address in a CC reply to a few hundred others. What a week you are having,” tweeted John Nash.