Network Browser v2.5.0 dropped support for SMB1.0 protocol as it is less secure, although this has caused some users with certain WiFi Routers or NAS devices to be unable to connect. I will add an option to re-enable SMB 1.0 support in a future update, but until then you can use the following link to revert to an older version of Network Browser for Android. You will have to enable installing packages from a non-store source, but that is easy to do.