Google Ad Software Disrupted for Publishers Large and Small

Google’s widely used advertising software for publishers suffered an outage of more than 2½ hours Thursday evening that affected numerous publications large and small.

During the outage, publishers who use Google Ad Manager couldn’t make their ad inventory available in exchanges for automated buying, according to publishers who use the technology. They also weren’t able to load any ads that the publication had sold directly, the publishers said.

Millions of websites use software from

Alphabet Inc.’s

GOOG -1.26%

Google unit to serve digital ads, including that of The Wall Street Journal and other major newspapers.

“We and all the publishers we work with are getting no ad revenue. Literally every company we know has been affected,” said Paul Bannister, chief strategy officer at CMI Marketing Inc.’s CafeMedia, a network of blog properties. He called the outage unprecedented in its scope and duration.

Google confirmed the outage in a tweet Thursday evening. “We’re investigating an issue affecting ad serving from Google Ad Manager and are working to address it as quickly as possible,” read the tweet from the Google Ad Manager account.

The service’s status dashboard said affected users were seeing “error messages, high latency, and/or other unexpected behavior,” and that Ad Manager wasn’t delivering ads for those users.

The dashboard later confirmed the restoration of service, saying the disruption lasted from 8:04 p.m. to 10:40 p.m. EST.

—Alexandra Bruell contributed to this article.

Write to Patience Haggin at patience.haggin@wsj.com

Google’s advertising software for publishers suffered an outage of more than 2½ hours Thursday evening.