With the clock ticking on whether a global hacking attack would wipe out his data, Bolton Jiang had no intention of paying a 21st-century ransom.
Since a week ago, when the malware first struck, Mr. Jiang has been busily fixing and replacing computers at the electronics company where he works in Shanghai. Paying is a bother, he said, and there was no guarantee he would get his data back.
“Even if you do pay, you won’t necessarily be able to open the files that are hit,” he said. “There is no solution to it.”
Tens of thousands of computer users around the world faced the same dilemma on Friday, their last chance to pay the anonymous hackers behind the ransomware attack known as WannaCry. The malicious software exposed the widespread vulnerability of computers and offered a peek at how a new type of crime could be committed on a global scale.
As part of the hacking, attackers demanded that individuals pay a fee to regain control of their machines, or face losing their data.
The latest strain of ransomware was particularly virulent, experts warned, because it had been based on software stolen from the National Security Agency. Law enforcement agencies in the United States and elsewhere have been hunting for the culprits, with attention focused on hackers linked to North Korea.
Despite a week of widespread disruption, the total ransom paid so far looks relatively modest. An online tracking system showed that the amount sent in the electronic currency Bitcoin to accounts listed by the attackers had begun to plateau on Wednesday, and had reached about $90,000 on Friday afternoon in Europe. Early estimates of what the virus could ultimately earn had ranged into the tens of millions or even hundreds of millions of dollars. Victims have seven days to pay from when their computers were originally infected, so the deadline will vary from case to case.
A number of people and companies have struck a defiant tone. The Japanese conglomerate Hitachi, which had been identified in the news media as a victim, declined to confirm those reports on Friday but said that it had no intention of paying a ransom and that it aimed to be fully secure against future attacks by Monday.
Nissan Motor, another Japanese industrial giant, also said it would not pay a ransom. Its factory in Sunderland, England, was affected, but the company said it had not lost data.
Owners of the more than 200,000 computers across the globe that have been hit by the malware face similar decisions. Those affected, including hospitals, government offices and universities, have lost access to business information, term papers and even medical records that could involve matters of life or death.
In Britain, whose National Health Service was one of the largest organizations affected by the ransomware, some medical institutions were…