Tens of thousands of households in Northern Ireland are still without power after high winds caused damage to the electricity network.
High winds led to fallen trees across Northern Ireland
Winds of up to 70mph swept across many areas as the remnants of Hurricane Gordon struck Northern Ireland.
Branches falling on power lines was the main cause of disruption, with Newry, Craigavon and mid-Ulster worst hit.
Motorists were advised to be careful in rural areas as some roads may still be affected by fallen branches.
Any faults can be reported to NIE's main incident room on 08457 643643.
NIE spokesman Robin Greer said it may be Saturday before all customers are reconnected.
"This is going to be a long day - I would expect the majority of customers to be back on supply by tonight," he said.
"On previous experience, we will be prioritising faults which are dangerous to the public and those which will get the largest number of customers back on supply.
"When you get the big faults, that's when you discover the smaller faults that lie further down the network, so I wouldn't be surprised if it's tomorrow before we get everyone back on to supply."
People were advised that if electricity supplies were lost, they should turn off major appliances such as cookers and take extra safety precautions, particularly if using candles or oil lamps.
Overall, more than 110,000 homes were left without power at some stage
Some overnight ferries were also affected but Stena said it hoped to accommodate passengers on Friday's later sailings.
The remnants of Hurricane Gordon have reached Northern Ireland
Meanwhile, a woman has been injured at the K Club in County Kildare after a branch of a tree fell near the golf buggy in which she was travelling.
The media centre for the Ryder Cup was also evacuated as a precaution due to the high winds.
Ryder Cup organisers fear more bad weather may mean playing an extra day.
Hurricane Gordon which passed Portugal's Azores Islands in mid-Atlantic on Wednesday, has been losing power as it hit cooler waters.
But its impact has been felt at the major golf tournament.
On Wednesday, organisers closed the K Club to spectators due to 40mph winds and have set Monday aside as a "reserve day" over fears that bad weather could delay proceedings.