I am working on a project that has a login page which uses LDAP Protocol to go out to a domain and retrieve user information. The application then validates the user off this information.

This works fine most of the time, but sometimes users are typing the correct information and they still cannot log in. If they try again in like 20 minutes, it will then work with the same login information. Also, sometimes the user will be typing their username in all lowercase and it will be fine, then they will need to sometimes type in in all uppercase to login. This seems to be part of the LDAP issue.

Does anyone know why this happens?