Update NHS staff can finally send emails to Hotmail accounts again, seven days after some healthcare workers complained to Microsoft that their messages were being blocked.

It’s not the first time the NHS has been shunned by Microsoft’s Hotmail. In May this year all addresses in the nhs.uk namespace were reportedly being blocked following a complaint about email originating from one of its IP addresses.

One NHS source told us that “neither Microsoft or NHS Relay [it's policy on email is here] appeared to notice or deal with the issue effectively when they were notified. I’m sure I don’t need to remind anyone that the NHS is the world’s third largest employer, and a lot of patients and candidates only have MS webmail accounts.”

He added that as of yesterday, NHS emails appeared to finally be reaching Hotmail accounts.

On Wednesday Microsoft told NHS staff affected by the issue that the firm would “coordinate with the domain administrator of your respective email provider to resolve your sending problem to Hotmail accounts.”

The Register asked Microsoft to explain why NHS Trust emails to Hotmail accounts had been blocked by its web mail servers, and also tell us why it’s clearly a recurrent problem for the software vendor.

We also asked NHS Relay to provide comment.

At time of publication, neither Microsoft or the NHS had got back to us. We'll update the story if they do. ®

Update

Microsoft has confirmed that the NHS's email troubles with Hotmail had now been fixed.

"The issue was caused by a high volume of SPAM messages being sent to Windows Live accounts which triggered Microsoft’s anti-spam software to block some emails," said a spokesman.

"Microsoft has since liaised with the NHS to implement new anti-spam and anti-virus systems which will prevent this from happening again.”

Meanwhile a Department of Health spokeswoman told us that an unnamed local NHS Trust email service had been "compromised" and confirmed Hotmail then blocked the nhs.uk domain.

"As soon as NHS Connecting for Health (NHS CFH) became aware of the issue, immediate steps were taken to rectify the matter. Once the Trust fixed their local systems and NHS CFH were able to confirm no further spam emails were being generated, Hotmail lifted their block," she said.

"While this issue happens rarely we are looking at putting in place controls to prevent this kind of problem reoccurring. It is important to note this issue only impacted locally run email systems and not the national NHS email service."

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