GPs, police and pharmacies are among UK services affected by a global outage on some Microsoft platforms.
Some GP surgeries have urged patients not to submit messages via their website while the problem remains, while several large police forces are urging members of the public to call if they want to make a report. MPs are also affected.
Microsoft has said the problem was caused by a higher-than-usual stress on its servers and that the fixes it had put in place were "not taking as expected".
Major airports and UK intelligence services have been unaffected by the outage, while a minister said officials were assessing the extent of the impact on government services.
Tim Frank, a GP in Penzance, told the BBC that they had received no emails today, and that if the problem with Microsoft's messaging platform Teams persisted, this could cause delays and affect patient care.
Practices in Hampshire and Shropshire have told patients to phone them or come into the surgery if they have an urgent need.
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What we know about the global Microsoft outage
A spokesperson for the National Pharmacy Association said the outage was affecting pharmacies'
