Millions of O2 customers have been unable to to make or receive calls or data since around Midday today.
The mobile phone company says it has now fixed the fault but that customers may still experience problems as full service returns.
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How to find out which machines are affected and what to do if yours is one of them.
The wintry theme continues.
Violent clashes between police and protesters erupted in Athens ahead of a farmers protest against pension cuts.