Looking for logging into the Error Failed For User site and are not getting the correct working link for it? In such a case, you can use the links given here by searching your desired login page in the search box. If the page is present on our website then you will get all the links related to the Error Failed For User site. After that you can login as usual with your login credentials.
https://support.microsoft.com/en-in/help/555332/login-failed-for-user-error-message-when-you-log-on-to-sql-server
https://stackoverflow.com/questions/17372606/sqlserver-login-failed-for-user
http://www.google.co.in/url?url=http://itproguru.com/expert/2014/09/how-to-fix-login-failed-for-user-microsoft-sql-server-error-18456-step-by-step-add-sql-administrator-to-sql-management-studio/
https://www.youtube.com/watch%3Fv%3DGDoOg_oeKEI
https://support.solarwinds.com/Success_Center/Server_Application_Monitor_(SAM)/Knowledgebase_Articles/SQL_Event_log_error_Login_failed_for_user_Domain_Username
https://kb.webtrends.com/articles/Problem/Attempt-to-perform-Data-Extract-returns-error-Login-failed-for-user-MACHINENAME-ASPNET
https://serverfault.com/questions/2218/sql-server-issue-login-failed-for-user-username
http://www.google.co.in/url?url=http://lexisnexis.custhelp.com/app/answers/answer_view/a_id/1086831/~/error%253A-login-failed-for-user-sa.-the-user-is-not-associated-with-a-trusted
https://knowledgebase.progress.com/articles/Article/login-failed-for-user-error-message-when-running-a-sitefinity-project
http://www.google.co.in/url?url=http://documentation.red-gate.com/display/SBU10/SQL%2BServer%2Berror%2B18456%2B-%2Blogin%2Bfailed%2Bfor%2Buser
https://comm.support.ca.com/kb/datamaker-connection-error-login-failed-for-user-sa-the-user-is-not-associated-with-a-trusted-sql-server-connection/kb000005192
https://bqekb.zendesk.com/hc/en-us/articles/360012713932-Login-failed-for-user
https://www.kb.blackbaud.com/articles/Article/51151