MikroTik frequently updates its communication protocol between Winbox and RouterOS. Version 2216 is often cited as the last stable release that fully supports RouterOS versions 5.x and early 6.x without connection dropouts or authentication mismatches. If you have a MikroTik router running RouterOS 5.20 to 6.40, older Winbox versions (including 2216) provide the most reliable connection.
For safety and full feature access, it is strongly recommended to download the latest version directly from the MikroTik Downloads Page WinBox - RouterOS - MikroTik Documentation winbox old version 2216 download full
Searching for "Winbox old version 2216" often leads to confusion because winbox old version 2216 download full