When a federated user tries to sign in to Microsoft Office 365 from a sign-in webpage whose URL starts with https://login.microsoftonline.com/login, authentication for that user is unsuccessful. The user receives the following error message: "Your organization could not sign you in to this service"
- Resolution 1: Disable Local Security Authority (LSA) credential caching on the AD FS server
- Resolution 2: Update the relying party trust with Windows Azure AD
This issue was resolved by converting the federated domain to standard (managed), and then converting it back to federated.
I am not sure if it was relevant to this issue (as some threads suggested), but when I initially converted my domain to federated, I had -SupportMultipleDomain switch on. I am assuming that it is not relevant because I still used the switch when I converted the managed domain to federated in the second time.