The first time a users clicks the accept button from a FE NXT web view invitation, they are directed to sign in and after signing in they receive the error:
Error: Unable to update database schema: A network-related or instance-specific error occurred while establishing a connection to a SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified) You will be directed to the sign in page.
This has been resolved as of March 2,2018 at 1:20 PM
Steps to Duplicate
From invite email, Click the link to accept the invitation
User is directed to Log in page and after logging in the error occurs.