ExTeam uses only one ODBC. For some reason, running under newer OS, you would need to set the ODBC for both x32 and x64. x32 ODBC are in a different registry than x64. Usually, I do set them up manually and not using the registry file for setting them up.
ODBC stands for Open DataBase Connectivity and it serves as an API for connecting to a remote or local database server.
(It's like a "Trusted local database connection", which don't require in most cases an username and password to connect to because the ODBC already have those credentials set).
For Windows 10, you can find both shortcuts for x32 and x64 in here:
C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Administrative Tools
Tutorial for x64 - you work on ODBC x64:
You must be registered to see links
For x32, it's the same tutorial, but you work on ODBC x32.
You only need one ODBC to be set up, which is MuOnline. Of course, if you changed the DSN in your server files config, those must match your ODBC name you've created.