Recently, Google began redirecting the URL used by M+Google departmental accounts to authenticate to Google, www.google.com/a/umich.edu, to U-M's single sign-on (SSO) login, which will not work with M+Google departmental accounts. You may use this temporary replacement URL for now: https://www.google.com/a/umich.edu/ServiceLogin?service=CPanel&passive=1209600&continue=https://mail.google.com. Please be aware that we cannot predict when this URL will no longer work for an individual account. We are aware of the impact to users and are working on a long term solution.
Note that the above only applies to individuals who wish to log directly into their departmental account. If you have delegated access to a shared account’s mailbox, the current method of switching from an individual M+Google account to a departmental M+Google account inside of Mail will still work.