Thousands of angry BT customers have been struggling with their email accounts because of problems with the broadband provider's server equipment.
A spokesperson for BT admitted that a small number of users had been affected "for a couple of days".
"We have people fixing a problem for a small number of customers who use BT Yahoo. The problem is quite small and is not affecting everyone. Some people's BT Yahoo accounts are working and others are not."
However, messages left by visitors on internet message boards indicate that problems accessing email have been happening since 11 March.
Other customers indicated that they would be taking their broadband custom elsewhere.
"After missing two employment opportunities and no way to talk to a customer service person at Yahoo, I will be closing my accounts," said one BT Yahoo user on the message board at yahoo.com.
BT said that it is not sure when the problem with the company's servers would be resolved and could not confirm how many users were affected.
BT Yahoo was formed in 2003, when the two companies teamed up to offer UK users broadband services.
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