On your Mac delete key.txt and the key folder and start the server.
Please post the terminal output.
Ramezanpour-MacBook-Pro:~ Ramezanpour$ cd desktop/macserver
Ramezanpour-MacBook-Pro:macserver Ramezanpour$ java -jar B4iBuildServer.jar
Build server version: 1.5
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2015-01-30 16:07:24.631:INFO::main: Logging initialized @2091ms
Loading default configuration file.
AppPath=/Users/Ramezanpour/Desktop/Macserver
Creating key for: 192.168.83.1
2015-01-30 16:07:30.127:INFO
ejs.Server:main: jetty-9.1.z-SNAPSHOT
2015-01-30 16:07:30.166:WARN
ejh.MimeTypes:main: java.util.MissingResourceException: Can't find bundle for base name org/eclipse/jetty/http/encoding, locale en_US
2015-01-30 16:07:30.229:INFO
ejsh.ContextHandler:main: Started o.e.j.s.ServletContextHandler@7d417077{/,file:/Users/Ramezanpour/Desktop/Macserver/www,AVAILABLE}
2015-01-30 16:07:30.236:INFO
ejs.AbstractNCSARequestLog:main: Opened /Users/Ramezanpour/Desktop/Macserver/logs/b4j-2015_01_30.request.log
2015-01-30 16:07:30.417:INFO
ejs.ServerConnector:main: Started ServerConnector@6e8dacdf{HTTP/1.1}{0.0.0.0:51041}
2015-01-30 16:07:31.106:INFO
ejs.ServerConnector:main: Started ServerConnector@467aecef{SSL-http/1.1}{0.0.0.0:51042}
2015-01-30 16:07:31.108:INFO
ejs.Server:main: Started @8776ms
Build server is ready
https://192.168.83.1:51042
http://192.168.83.1:51041
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but 192.168.81.1 is not my ip !