PlusNet deletes customers' emails again

In an echo of last year's troubles, the ISP accidentally deleted a number of its customers' emails during a hardware upgrade

PlusNet has again lost some of its customers' emails, echoing troubles experienced by the internet service provider last year.

In July 2006, the ISP lost thousands of customers' emails — totalling around 700GB of data — after an engineer accidentally deleted the contents of a live server rather than a backup server. This time the deletions took place as the result of a new spam appliance being installed. The full extent of the deletions is not yet known.

Customer support officer Bob Pullen wrote in a service note on the ISP's website on Thursday that the installation of the spam appliance resulted in "some email" queuing on the appliance before being delivered to its mail servers.

"The decision was taken to roll back the changes late afternoon at which point new email should have been getting delivered immediately and older email should have been in the process of getting dequeued," wrote Pullen. "Unfortunately this was found not to be the case and our on-call engineers were contacted yesterday evening to investigate further."

PlusNet estimates that around 10 percent of legitimate emails that were "dequeued" from the new appliance were falsely labelled as spam, and subsequently "black-holed". According to Pullen's posting, 10 percent of legitimate emails received between 5pm and 11pm on Wednesday night were also deleted. "These mails will not be recoverable and we recommend customers who have not received email that was sent yesterday to ask the sender to re-send where possible," wrote Pullen.

The ISP is now investigating the incident. In a statement released on Thursday, it apologised to affected customers and promised that its "email platform is currently working normally".

PlusNet was bought by BT at the end of last year, largely for its CRM system. Aside from last year's mass email deletion, PlusNet also suffered a significant power outage in August 2006. Earlier this year, the ISP was forced to admit that many of its customers' email addresses had been stolen, leading to some customers experiencing a deluge of spam.