Yahoo and BT emails have crashed for hundreds of users up and down the UK.
BT is the biggest broadband provider in the UK and also supports the Yahoo email system.
Undiagnosed problems have left customers unable to access their accounts since around 11am.
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According to live outage detector site downdetector, 45 per cent of affected customers are having email access problems
According to live outage detector site downdetector, 50 per cent of affected users are having internet issues and 45 per cent of customers are having email access problems.
Issues began around 11am and hundreds of complaints flooded in over the next two hours.
Approximately three per cent of complaints are regarding problems with the phone service.
BT, which also owns Yahoo, has admitted issues with Yahoo email access.
In a statement on the site, the BT said: ‘Some BT Yahoo mail customers may be experiencing logging into their email account.
‘We are working to resolve this. In the meantime please try to access using webmail.’
But while third-party apps seem to be failing, some users claim they are experiencing problems with desktop computers.
MailOnline has approached BT for comment.
BT has crashed for hundreds of users up and down the UK. The biggest broadband provider in the UK is experiencing significant connectivity issues with many customers left without internet