Scores of BT Business customers have reported being unable to send emails after the blacklisting of an IP address that the telco has blamed on security firm MessageLabs.
Customers have vented their fury on BT's dedicated business forum, insisting that the company has failed to give the problem the attention it deserves.
"I am not able to send emails to certain addresses," wrote 'Katie_W'. "The people I am emailing, I regularly contact, and it's not happened previously. I have double checked and I am typing in the correct email address."
A moderator on the forum named Frances Midgley admitted to an issue with IP addresses, but gave no information on when the problem might be resolved.
"We are aware that an organisation has chosen to 'blacklist' IP addresses which include those provided to BT customers, as well as those of other organisations, alleging that some of these customers' computers are being used to create spam," she said.
However, the response has failed to appease angry customers. "The answer posted by BT is quite frankly ridiculous," wrote 'Jayvr', while another customer, Malcolm Sleath, wrote: "BT is offering a non-answer as far as I am concerned."
Sleath expanded on the issue in a blog post. "BT have confirmed on the phone there is a problem, which they hoped to have resolved by this morning, but I am still getting mails bouncing back and there is no information on the web sites or status lines BT have suggested I monitor," he wrote.
BT's service status page shows no acknowledgement of the issue, but the company confirmed the problem to V3.co.uk and cited MessageLabs, which is now known as Symantec Hosted Services, as the source.
"BT Business is aware that a small number of customers have reported 'bounce backs' when sending emails to people using MessageLabs anti-spam solutions," a spokesperson said.
"BT is currently working with MessageLabs to understand the root cause of the bounce backs and to resolve the issue. We apologise for any inconvenience caused."
Update 17:00: BT has said that the problem is now fixed.
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