Where’s my Internet? ISPs ready for DNSChanger calls.

This story has been updated since it first appeared June 6 to reflect that the deadline has passed.

Time’s up. The thousands whose computers are still infected with DNSChanger likely lost their ability to access the Internet at 12:01 a.m. EDT June 9, when replacement servers handling traffic redirected by the malware were taken offline.

For those computers, the end came after months of efforts by the FBI, other federal agencies, Internet service providers and the DNSChanger Working Group alerting people to test for infection and fix their computers if they were compromised.

“We’ve reached a critical point,” Bob Elek, spokesman for Verizon, which is part of the working group, said late last week. As many as 10,000 Verizon customers are believed to still be infected, and hundreds of thousands worldwide. “Hopefully this last push will cause people to put two and two together.”

Related coverage:

Hundreds of thousands at risk as DNSChanger deadline looms

The working group has for months had tools and instructions online to test for and fix DNSChanger infections. Unfortunately, the people who need it now probably will not be able to reach them. So what can they do?

As of Monday morning, the best solution for anyone who has lost access probably will be to call your service provider’s help desk. Major Internet service providers are prepared to field the calls, but cleaning up the infections is not a simple process and many people might need professional help.

The Domain Name System acts as a directory for the Internet, translating URLs to numerical IP addresses used to direct communications. DNSChanger is malware that allowed criminals to hijack Web traffic by directing DNS requests to their own malicious servers for resolution.

Discovered in 2006, it eventually infected more than 4 million computers and routers before the FBI shut down 100 command and control servers in a U.S. data center in November. To keep infected users from going dark, it obtained a court order allowing Internet Systems Consortium to operate clean DNS servers using the gang’s IP addresses for 120 days. This was extended to July 9 to give more time to clean up the infections. No further extensions are expected.

The latest figures from the DNSChanger Working Group show that more than 300,000 unique IP addresses still were communicating with the temporary ISC servers on June 11. The largest batch of those addresses, nearly 70,000, were in the United States. Italy came in a distant second with 26,494. The security firm Internet Identity reported on June 28 that it found that 12 percent of Fortune 500 companies had computers that remained infected, as did two federal agencies.

Service providers have attempted to contact customers who appear to still be using the temporary DNS servers, but with limited success.

“We’ve been working with law enforcement since November,” Elek said. “We had about 13,000 customers who were infected.” The company used e-mail, phone calls and U.S. mail to notify them of the problem. “People being people, we had a 10 to 15 percent success rate. That’s consistent with other industry reports.”

Part of the problem is that phony alerts for antivirus and malware removal tools are a common online scam, so many people disregard such notices without checking them out.

Beginning Monday, infected Verizon customers will be put into to a “soft-walled garden” when they go online, where a  landing page will tell them of the problem and offer options for fixing it. They can get instructions for doing it themselves, can get 30 days of free tech-support service, or can be referred to third-party support. This redirect will continue through July. After that, users will go nowhere.

“The malware is way down deep” in the computer, Elek said. “But it can be fixed.”

The DNSChanger Working Group site is a good one-stop shop for testing to see if you are infected and for information about remediation. It outlines five steps for fixing the problem:

1. Back up your files.

2. Either you, a professional or someone you trust can clean up the malware using tools and guidance available in a number of reference guides.

3. Check your computer’s DNS settings to make sure they are correct and not connecting you to a DNSChanger server.

4. Check your home router to make sure its DNS settings are correct.

5. DNSChanger also can include keystroke monitoring and other spyware, so it would be a good idea to check bank statements and credit reports as well as change passwords on any online accounts.

The site also provides links to nine free tools to remove threats, but recommends that it is best to follow procedures in a number of self-help cleanup guides, which usually involve using several of the tools to ensure that all problems are cleaned up.

But remember, many of these resources are online, and it will be much easier to deal with problems now than to wait until you are thrown offline.