Set its value to your Java installation path (e.g., C:\Program Files\Java\jre1.8.0_311 ). Click .
Because the legacy discovery tool is no longer supported, it is recommended to use newer official or community-driven utilities: UBNT Discovery Tool V2.5.1 and JAVA on windows 10
Right-click the .bat file → Run as administrator . This grants the raw socket access required for Layer 2 discovery.
By following this updated approach, you can still leverage the quick, effective capabilities of the on modern Windows 10 environments. ubnt discovery tool v251 and java on windows 10 updated
@echo off set JAVA_HOME=C:\Program Files\Zulu\zulu-11\bin %JAVA_HOME%\java.exe -Djava.net.preferIPv4Stack=true -Djava.security.egd=file:/dev/./urandom -jar UBNT_Discovery_Tool_v2.5.1.jar
Since you may not want to downgrade your global Java installation, you can use these methods:
If you already have Java installed but the tool won't launch, the issue is usually pathing or security settings. Set its value to your Java installation path (e
Ensure Windows Firewall is not blocking the tool, as it needs to listen on UDP port 10001 to discover devices.
If the command is not recognized, install the JRE from Oracle. 3. Running the JAR File (Fixing "Open With" Issues)
The main issue with using the UBNT Discovery Tool v2.5.1 in 2026 is its reliance on older Java technology. Modern Java updates (JRE 8 and above) include security enhancements that may block older jar files. Furthermore, Java 9 and newer versions introduced structural changes, making it difficult for the old, un-updated .jar file to function. This grants the raw socket access required for
Your current (type java -version in Command Prompt) Whether you are scanning across different subnets or VLANs
Open Settings > Apps > Apps & features . Remove any Java versions newer than 1.8.0_300. If you have Java 11 or 17, uninstall them first.
Below are five practical solutions, ranging from quick workarounds to more robust, containerized approaches. Choose the one that best fits your technical comfort level and network environment.