"As cybercriminals become more sophisticated, there is simply no way for customers to protect themselves against threats unless they update their systems", Mr Smith said.
More than 75,000 similar attacks reportedly happened in nearly 100 countries, with Russia, Ukraine and Taiwan hardest hit, according to the cybersecurity firm Avast. New versions of the worm are expected, the experts said, and the extent - and economic cost - of the damage from Friday's attack were unclear.
Fortunately, a 22-year-old British researcher and 20-something American security engineer discovered a "kill switch" and unregistered domain that halted the attack, reports the Associated Press.
"If you have a scheduled appointment you are advised to attend as normal unless you are told otherwise". Companies across the company are expected to be running checks and updating software today.
Europol executive director Rob Wainwright had warned on Sunday the situation could worsen when workers return to their offices on Monday after the weekend and logged on.
"It seems inconceivable that organisations such as the NHS are prepared to jeopardise highly confidential patient data or critical infrastructure through inadequate cyber security that relies heavily on out-dated anti-virus technologies, when effective alternatives like file-regeneration are available".
Kane wants hat trick in WCQ vs Scotland
If I could have another season like this then hopefully I can get there. "It would be a fantastic achievement", Kane added. Kane has already turned his attention to 2017-18, targeting 100 goals as he now sits on 75 Premier League strikes.
Adams' comments 'sad' - Arsenal's Wenger
They've won eight of 10 games played on Merseyside on the final day and averaged 2.7 goals a game during that sequence. They have earned four successive league victories at the Emirates Stadium, keeping clean sheets in all of them.
The Flynn News is Fake News
In her testimony, Yates said that she had called McGahn the Monday after they met to tell him the material was ready to review. He pushed back on Yates' comments addressing the firing of Michael Flynn as Trump's national security adviser.