[Error] You do not have an account on this site

Problem/Motivation

Some people will get the following message while trying to log in even if the account exists in Drupal:

"You do not have an account on this site. Please contact a administrator."

There's a bug with the o365 module where it doesn't ignore cases, for example in Azure AD, an email would look like this (first letter uppercase): Firstname.Lastname@domain.com but in Drupal, the email is firstname.lastname@domain.com (all lowercase) and the account wouldn't match so the person would get the error.

To fix the issue, we need to log in to Azure AD and check if the email of the user has some capital letters, then go back to Drupal and update the email to match the case.

Steps to reproduce

Simply create an account in Drupal with lower case/upper case that does not match the Azure AD account and try to log in.

Proposed resolution

Update the o365 module to ignore cases for email addresses.