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Currently supported: All versions

[Solved] Developing offline

Jay Avery
in Modder Support

Featured Replies

Posted

This weekend I'm going to be travelling and I'd like to be able to bring my laptop and work on my mod. But I just experimented with turning off my internet and then trying to run my mod from eclipse, and I got a crash:

 

 

[14:48:21] [main/INFO]: Logging in with username & password
[14:48:23] [main/ERROR] [GradleStart]: -- Login failed!  Cannot contact authentication server
Exception in thread "main" java.lang.RuntimeException: com.mojang.authlib.exceptions.AuthenticationUnavailableException: Cannot contact authentication server
at com.google.common.base.Throwables.propagate(Throwables.java:160)
at GradleStart.attemptLogin(GradleStart.java:103)
at GradleStart.preLaunch(GradleStart.java:59)
at net.minecraftforge.gradle.GradleStartCommon.launch(GradleStartCommon.java:81)
at GradleStart.main(GradleStart.java:26)
Caused by: com.mojang.authlib.exceptions.AuthenticationUnavailableException: Cannot contact authentication server
at com.mojang.authlib.yggdrasil.YggdrasilAuthenticationService.makeRequest(YggdrasilAuthenticationService.java:85)
at com.mojang.authlib.yggdrasil.YggdrasilUserAuthentication.logInWithPassword(YggdrasilUserAuthentication.java:78)
at com.mojang.authlib.yggdrasil.YggdrasilUserAuthentication.logIn(YggdrasilUserAuthentication.java:61)
at GradleStart.attemptLogin(GradleStart.java:98)
... 3 more
Caused by: java.net.UnknownHostException: authserver.mojang.com
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at sun.security.ssl.SSLSocketImpl.connect(Unknown Source)
at sun.net.NetworkClient.doConnect(Unknown Source)
at sun.net.www.http.HttpClient.openServer(Unknown Source)
at sun.net.www.http.HttpClient.openServer(Unknown Source)
at sun.net.www.protocol.https.HttpsClient.<init>(Unknown Source)
at sun.net.www.protocol.https.HttpsClient.New(Unknown Source)
at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect(Unknown Source)
at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getOutputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getOutputStream(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getOutputStream(Unknown Source)
at com.mojang.authlib.HttpAuthenticationService.performPostRequest(HttpAuthenticationService.java:77)
at com.mojang.authlib.yggdrasil.YggdrasilAuthenticationService.makeRequest(YggdrasilAuthenticationService.java:66)
... 6 more

 

 

Is there a setting I can change to allow me to run Forge while not connected to the internet? Surely it is possible, since you can play vanilla Minecraft offline?

  • Quote

    (I think) Minecraft in a dev environment only tries to connect to the authentication server if there's both a username (email) and password available from the program arguments. If you have them, you might want to check if removing those fixes the issue.

    Don't PM me with questions. They will be ignored! Make a thread on the appropriate board for support.

     

    1.12 -> 1.13 primer by williewillus.

     

    1.7.10 and older versions of Minecraft are no longer supported due to it's age! Update to the latest version for support.

     

    http://www.howoldisminecraft1710.today/

  • Quote
    • Author

    Oh, thanks for the tip - that's done it! I just removed my username from the run configuration arguments and it ran offline with no problems.

  • Quote

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