CRM biz Zoho left millions of customers fuming on Monday when it briefly lost control of its critical Zoho.com domain name, bringing its services to a grinding halt.

Around 9am Pacific Time, its staff freaked out after the Zoho.com homepage came up blank. The domain name had been blocked, a message from the company's registrar stated.

Thousands of messages from angry Zoho customers, who were unable to reach their databases and messages, nor access their email campaigns, started flooding in, causing the India-headquartered company to post a panicked message on Twitter.

"Our Zoho.com domain is blocked and Tierra our domain registrar is not responding," the tweet read. "Can someone help us reach their senior executive team?" it asked with a picture listing Tierra's senior executives.

An hour later, Zoho CEO Sridhar Vembu was still scrambling: "We are working hard to identify why the domain was taken down by the registrar in the first place. Once we do that, we will take alternative steps so this never happens. We apologize sincerely but this issue is well beyond our control and our domain was taken down with no notice!"

Meanwhile, customers started contacting Tierra directly with one posting a chat conversation in which the registrar claimed Zoho had been cut off because it failed to respond to security concerns.

It sounds as though some phishing emails were sent using Zoho's customer messaging services, and the registrar was fed up with it.

"Zoho was suspended after repeated contact requesting them to take action against phishing emails. They didn’t, so we had to suspend them," the note read.

I see...

That seemingly improbably series of events was then confirmed by Vembu who seemed less than impressed with Tierra's customer service. "There were a total of 3 complaints in 2 months and we took action on 2 of them immediately and one is pending investigation," he shot back on Twitter. "We serve 40 million users. 3 complaints in 2 months."

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We can see why Vembu was not impressed. We contacted Tierra to ask about its decision to cut off a software-as-a-service company with 5,000 staff, roughly 40 million users globally, and an estimated $400m-plus in annual revenues, from the internet based on what appear to be a few unanswered emails.

The main telephone number listed on Tierra's website has been disconnected. When we got through to the San Diego-based company on a second number, we were told that no one there would answer our questions.

"We can't respond to queries about this domain name. Have a good day," said a woman before abruptly hanging up. The domain has since been restored after several hours offline.

So, not a great advertisement for Tierra – which didn't seem to realize it was handling the domain name for a massive business with millions of users and seemingly failed to contact the company directly before pulling its entire internet presence.

And likewise, not a great sign that Zoho – which registered its dot-com back in 2004 – has not considered moving a fundamental business asset to a more secure status. Larger registrars offer special services and protections for important domain names, such as not making any changes until they have spoken to a specific named individual.

Clearly neither Zoho nor Tierra has that arrangement – which is common for large businesses – in place. And it has made them both look rather stupid today.

Market-nooooooooo!

It's not unheard of, even now, for domain names to go wandering. In July last year, billion-dollar online marketing company Marketo failed to renew its main dot-com and the domain was moved by the organization's registrar, Network Solutions, to its "pending deletion" pile after it failed to pay the $35 required for another year's registration.

The result was not only the disappearance of its website and email but also the instant loss of millions of tracked hyperlinks, forms and client reports that all rely on the internet address to work. Its CEO also scrambled to fix the issue within a few hours, but it took a day for everything to get back working again.

The lesson for all is very, very simple: check on the status of your company's main internet addresses and make sure you talk to your registrar about what you can do to protect it. They might charge you a hundred dollars or so but as Zoho's CEO will no doubt confess following today, it's probably worth it to stop your business grinding to a halt. ®