Columbia University web authentication (CAS) will be upgraded between 6am and 7am on June 10, 2020. During the upgrade, there may be a brief interruption in service of less than a minute. Before logging in for the first time after the upgrade, end users will be asked to clear browser cache, close down all browser tabs and windows and restart their browsers. For instructions on clearing browser cache, see: https://cuit.columbia.edu/clear-cache