If you're and admin and a user reports getting a 500 error page when they are trying to login, there are a few places to begin troubleshooting.
First, you'll want to login to Keycloak on your deployment and verify the user exists in that console. You'll also want to verify their account has an accurate first name, last name, and email address. If any of the values are missing, please fill them from the Keycloak console with the proper information.
Next, you'll want to check the user's data in the mongo database. The mongo console can be accessed by going to Admin > Advanced > MongoDB
Here is the query you'll want to run (please modify the domino_user to the user you are investigating):
For example, looking up user j_jones would look like the following:
Once again, please verify the user has the correct information - you'll want to focus on first name, last name, and email address - but skim it all to be safe.
In addition, please verify the user has the IdpId value set.
If only the IdpID value is missing, please follow the steps in this article to insert the missing value: Error-activating-deactivating-user-User-user-does-not-have-idpId-set-
If any of the other information in mongo is incorrect, please reach out to Domino support and they will help you get the problematic account back on track. We highly recommend admins do not make any mongo edits without Domino guidance, as any errors can cause major issues for the entire Domino deployment.