The web has an inclusion problem: it overwhelmingly caters to speakers of the English language. That’s most clearly seen in the fact that over half of all websites are in English. But there’s a more insidious issue at work—even the way people navigate to websites is set up to exclude non-English language users, according to a new report from ICANN, the non-profit that governs internet addresses.

The problem lies with top-level domains, the .coms, or .orgs that form a web address. When the internet was birthed, there were just seven top-level domains. From there, the number grew gradually. Then, in 2011, ICANN approved a plan to greatly expand the diversity of top-level domains, in the name of promoting consumer choice. Internet users could now go to web addresses written in Mandarin (.网络), French (.musée), or with top-level domains longer than the traditional three-character limit, like .bank, .berlin, or .google.

The proliferation of new domains triggered a problem. The creative new addresses often weren’t recognized by major systems on the web that had been programmed to accept three-letter domains, the new report says. This matters because the internet’s growth depends on users from developing countries, and they want to use their own languages online, says Ram Mohan, who chairs a group at ICANN tasked with solving the problem. ”It’s growing in China, India, Turkey, Malaysia, places like that. That’s where the next generation of the internet is coming from,” he says.

Here’s an example from the report of how domain names could screw up someone’s online transaction: Airlines use a system to transfer information among each other that can’t render Chinese characters and other non-Latin scripts. The system would reject or mishandle data for a traveler with Chinese characters in her email address, the report says. Problems like these are barriers for millions of people who will stay offline because of a lack of local language content. “Seventeen million of them will come online using primarily their local language to access the internet,” Mohan says. That translates to $9.8 billion a year in lost e-commerce revenues, according to the report’s estimate, which uses a global average.

There’s no simple fix for the problem. Mohan and his group at ICANN must convince the world’s major email providers, social networks, and database companies—any major provider of internet services—to ensure their systems work with international domain names, and newer top-level domains. This is the concept of “universal acceptance.” It means engineers must check to make sure their systems don’t automatically reject a user trying to register with an email address that’s five-characters long, or written in non-Latin script. “You have leaders at these companies who are not even aware this is a problem,” he says.

Fortunately for Mohan, the web’s biggest companies are backing his mission, including Microsoft, Amazon, and Google. (Facebook and Twitter have been slow to get on board, Mohan says.) He’s embarking on a major awareness campaign this year, starting with this report. There’s a chance the job could be done for most of the internet’s users within two years, but Mohan acknowledges it’s going to be a challenge: “It’s a pretty big problem, it’s a global problem. It affects the entire internet.”