"An issue with Autodesk’s Identity Authorization Service impacted our customers’ ability to login to Autodesk Products and Services for several hours on November 17," said Raymond Deplazes, senior manager of technology communications at Autodesk. "This issue has now been resolved and all Autodesk Products and Services were returned to full service. We are sorry for the frustration this caused customers and are immediately taking steps to ensure we prevent this from occurring again in the future."

One contractor ENR spoke to said all of the services it uses were back up and running by the morning of Nov. 18 after a "brief hiccup" interrupted service that morning as well. Another VDC professional said it was impossible to continue work on their projects on Nov. 17 because of the nature of the cloud services it uses, as any changes made offline in its Autodesk products could not be saved and would be overwritten when the cloud services came back online.

User @BardenLyze wrote on social media site Twitter: "Any update on time this coming back online Autodesk? Got all our 500+ projects in BIM360 and at standstill."

Other users wrote to @Autodesk about getting reimbursed a portion of their subscription costs for losing a day of work. 

The Autodesk Identity Authorization Service is a cloud-based service that stores and manages login information for all of Autodesk's cloud products. Autodesk described the problem as a "degradation" of the service which could have been caused by anything from errors on the servers to too many individual cloud servers going offline. Autodesk did not say how the degradation was fixed, but assured users steps were taken to stop it from happening in the future.