To run v2.5.1 successfully, your system must meet specific criteria that deviate from standard modern setups:
Because the Ubnt Discovery Tool sends UDP broadcast packets to locate devices on your subnet, the Windows Defender Firewall will frequently block its traffic without throwing a visible error. Press Win + R , type control firewall.cpl , and hit Enter.
Ensure both and Public checkboxes are ticked for all Java listings. ubnt discovery tool v251 and java on windows 10 updated
Overview
The software requires a Java Runtime Environment (JRE) to function. Windows 10 updates and modern Java security protocols often break this tool. Launching the application frequently results in errors, crashes, or a frozen interface. To run v2
If the command is not recognized, install the JRE from Oracle. 3. Running the JAR File (Fixing "Open With" Issues)
Because v2.5.1 is officially deprecated and unsupported, Ubiquiti recommends transitioning to modern alternatives that do not require Java: Overview The software requires a Java Runtime Environment
Verify the installation by opening Command Prompt and typing: java -version . Ensure it outputs 1.8.0_xx . 2. Configure Environment Variables