Twitter says “an internal configuration change” is responsible for an outage that lasted for about an hour.

Thursday’s outage began before noon PT; some users were able to access Twitter again by 12:45 p.m. Twitter says some users may be able to access the service as the company works on a fix.

The disruption appeared to affect both web and mobile app users. According to Down Detector, a website that tracks outages, problems were reported from the U.S., Europe and elsewhere.

Outages were widespread in Twitter’s early years, so much so that a cartoon “fail whale” the company would put up during outages came to symbolize Twitter almost as much as its little blue bird icon. In recent years, outages have been less common.

(AP)