Trend Micro has promised an internal investigation into a bug contained in one of its security product updates that blocked all incoming emails containing the letter P.
Although the number of customers reporting the flawed update was low, the reseller channel in the US was notified because the company said it wanted to be as open as possible.
But UK resellers were not informed.
The bug occurred in the vendor's anti-spam update, Rule #915, for Trend Micro eManager, an email content security product that provides content filtering, spam blocking and reporting.
Trend claimed that there had been no need to advise UK resellers because the bug had been dealt with swiftly.
"A new rule, #916, was released before it had a major impact on the UK, so we felt there was no need to inform the channel," explained Raimund Genes, president of European operations at Trend.
"Only a few customers were affected in Europe - fewer than 10. Luckily the problem was minimal but it should never have happened.
"We thought it was bullet-proof, but no software is bug-free and we will have an inside investigation to find out how it happened."
Bernie Dodwell, sales and marketing director at Allasso, said: "We don't sell that product but, as a general principal, any vendor selling security software that discovers a flaw should, as a professional organisation, hand that information down to everybody.
"Even if just one customer phones up and a reseller doesn't know about it, it is embarrassing. Customers must be informed so they know how to download the update."
Dave Ellis, director of e-security at Trend Micro reseller Unipalm, said: "I wasn't aware of the problem with the product, but there are different levels of alert and the information flow with Trend Micro is normally good, so I feel comfortable about that decision.
"Sometimes you can be hit with false negatives or false positives so the important stuff gets lost in the noise and you can't focus on what really matters."
Customers can learn how to recover emails inadvertently quarantined by the flawed update by calling Trend Micro or by clicking here.
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