Brit biz Sage left UK customers without critical software - including its Payroll suite - after toppling offline.
After the firm's web servers for sage.co.uk went down, the business programs were unable to connect to the website to automatically check for upgrades.
"Yesterday we experienced an outage on sage.co.uk. This meant people couldn't visit our UK website and some of our desktop software was temporarily affected, taking slightly longer than normal to open the programs," the company said in an emailed statement.
Sage said its website was offline until 8pm, some ten hours after users' complaints started appearing on Twitter at about 10am. The firm kept customers updated on its social networking pages, and told clients they could still access services directly online instead of through their software.
The Newcastle-headquartered company said it was still investigating the cause of the outage. ®