Godwin Paul Vincent

If you have a SharePoint On Premise installation with a Custom Login Page , you might encounter issues working with CSOM. The error would be primarily related to Authentication Failure. The following solution worked for me. Step 1 : The Custom Login Page should be placed in IIS Virtual Directory. As a general practise the custom login page is normally placed in the 15 Hive Layouts folder. Move/Copy the ASPX file of your custom login page from the 15 hive layouts folder to  the following folder in IIS Virtual directory of the concerned Web Application: “C:inetpubwwwrootwssVirtualDirectories<yoursite>_forms” Step 2 : Edit the Custom Login page file to make sure the master page url is correct. After the movement of the ASPX file, open the file in a notepad and check for the  MasterPageFile  value and change it to the following  =”~/ _layouts / 15 / simple . master “. Step 3 : Change the Custom Login Page Url in Central Administration. Navigate to Central Admin and change the Url def