However staff beginning the working week have been told to be careful.
The incident has not affected electricity supply because the infected computers were used mainly for administrative work, Taipower spokesman Lin Te-fu (林德福) said.
But Health Secretary Jeremy Hunt failed to address the NHS cyber attack when he was approached by BBC reporters on Monday morning.
It's a rare occurrence that I find myself defending Microsoft's actions but the rampant finger pointing after the WannaCrypt ransomware is an all-to-often reminder that Windows should be treated as a mission critical application and not a microwave that warms up your food.
It also threatens to delete the files if payment is not made within seven days.
Telefónica: Spanish authorities confirmed the Spanish telecom company Telefónica was one of the targets, though the attack affected only some computers and did not compromise the security of clients' information.
Many firms employed experts over the weekend to try to prevent new infections. After "WannaCry", it released an emergency patch for older systems too.
Auto manufacturer Renault said one of its plants, which employs 3,500 people in Douai, northern France, wasn't reopening Monday as technicians dealt with the cyberattack's aftermath. Seven of the 47 affected trusts were still having IT problems Monday.
South Korea: Only nine ransomware cases.
Beijing has previously said the proliferation of fake news on US social media sites, which are largely banned in China, is a reason to tighten global cyber governance.
United States accuses Assad of mass atrocities at Syrian prison
It said the government of President Bashar al-Assad then uses the crematorium to destroy the bodies. The crematorium would be used to cover up the evidence , he said.
"We don't expect this to be a sophisticated group", said Wellsmore.
Russian President Vladimir Putin said: "Russia has absolutely nothing to do with it".
Basic protocol such as stressing that workers shouldn't click on questionable links or open suspicious attachments can save headaches.
The message from the UK's National Crime Agency was "do not pay!" - there is no guarantee that systems will be restored. The assault infected computer networks around the world, its perpetrators unknown and its goal uncertain, although it may have been nothing more than an attempt to extract money from its victims.
Becky Pinkard, from Digital Shadows, a UK-based cyber-security firm, also said it would be easy for the initial attackers or "copy-cat authors" to change the virus code so it is hard to guard against. "Talk about a wake-up call", Hypponen said.
"Since March, the government has been on high alert".
"We have seen vulnerabilities stored by the Central Intelligence Agency show up on WikiLeaks, and now this vulnerability stolen from the NSA has affected customers around the world. An equivalent scenario with conventional weapons would be the USA military having some of its Tomahawk missiles stolen", Smith said. "Once upgraded, the windows operating system becomes more secure", he said.
The malware attack, which began on Friday and has been linked by some researchers to previous hits by a North Korean-run hacking operation, leveraged a tool built by the NSA that leaked online in April, Microsoft says. Over the weekend the company took the unusual step of releasing a similar patch for Windows XP, which the company announced in 2014 it would no longer support.
Microsoft distributed the patch two months ago, which could have forestalled much of the attack, but in many organizations it was likely lost among the blizzard of updates and patches that large corporations and governments strain to manage. "With digitisation, there are several vulnerabilities", said Krishnashree Achuthan, CEO of Amrita University's Center for Cybersecurity Systems and Networks. Tough - time-consuming, expensive and complex.
Dowling says that the best way to prevent an attack is to keep computer operating software updated.