The widely reported Kama Sutra malware was set to overwrite infected users' files on Friday, but according to most observers, it did little damage.

This was certainly the case with Microsoft's toll-free virus support hotline in the US, where the worm's arrival had little effect, according to Stephen Toulouse, security program manager at Microsoft's security response center.

"It's a little early to fully understand the impact, but right now we and the antivirus partners are not seeing any widespread impact from this," he said on Friday.

Though Toulouse was unable to say how many calls the Microsoft hotline had received, he believed it was minimal. "I'm sure if I went back there might be one or two cases," he said.

Earlier last week, security experts had predicted that there would be little widespread disruption from the worm.

"There's been way more attention given to it in the media than it deserves," said Russ Cooper, senior information security analyst at Cybertrust. The dramatic nature of this worm's behaviour, with its file-destroying instructions, and inflated reports of infections have helped fuel media interest, he said in an interview last Tuesday.

Also known as Win32/[email protected], Nyxem, Blackdoom, [email protected] and Tearec, the worm needs a fair bit of help to infect a user's machine. Kama Sutra is blocked by virtually all antivirus protection software, and even those without security software must somehow be tricked into clicking on a PIF (Program Information File) attached to an email in order to execute the program.

The fact that Microsoft has had so few calls on the issue shows that customers are getting savvier about computer security, and are increasingly following Microsoft's advice to install antivirus software and be careful about clicking attachments, Toulouse said. "It shows us that that guidance is starting to take hold," he noted.

Was Kama Sutra a non-event? Toulouse declined to answer that question. "It's a little early," he said on Friday afternoon. "I don't want to jinx it."

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