To connect users to SAP BO Platform for microsoft sharepoint with the help of BW authentication, one need to use SAP SSO within launchpad unless connecting direct from the EP portal. And for this purpose one need to have a mysapsso2 token. And also configure one type (LDAP/Active Directory/Enterprise) instead of aliasing SAP users to the non-SAP users. It is also mandatory to configure SNC or STS for the purpose of backend SSO part.
By doing this you’ll be able to implement single sign on for Microsoft Sharepoint.