IntelliJ IDEA 无法启动，在启动画面处冻结，并在控制台中显示“未能创建子事件循环”答案

【问题标题】：IntelliJ IDEA don't start, freezes at the splash screen with "failed to create a child event loop" in consoleIntelliJ IDEA 无法启动，在启动画面处冻结，并在控制台中显示“未能创建子事件循环”
【发布时间】：2022-01-28 19:58:47
【问题描述】：

C:\Program Files\JetBrains\IntelliJ IDEA 2021.3.2\bin>idea.bat 2022-01-28 11:43:55,396 [     86]   WARN -
llij.ide.plugins.PluginManager - id redefinition ([row,col,system-id]:
[2,3,"product classpath"]) 2022-01-28 11:43:56,728 [   1418]  ERROR -
llij.ide.plugins.PluginManager - java.lang.IllegalStateException:
failed to create a child event loop
java.util.concurrent.CompletionException:
java.lang.IllegalStateException: failed to create a child event loop
        at java.base/java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:314)
        at java.base/java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:319)
        at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1702)
        at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.exec(CompletableFuture.java:1692)
        at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:290)
        at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1020)
        at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1656)
        at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1594)
        at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:183)
Caused by: java.lang.IllegalStateException: failed to create a child
event loop
        at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:88)
        at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:60)
        at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:49)
        at io.netty.channel.MultithreadEventLoopGroup.<init>(MultithreadEventLoopGroup.java:59)
        at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:87)
        at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:82)
        at org.jetbrains.io.BuiltInServerKt.multiThreadEventLoopGroup(BuiltInServer.kt:158)
        at org.jetbrains.io.BuiltInServerKt.access$multiThreadEventLoopGroup(BuiltInServer.kt:1)
        at org.jetbrains.io.BuiltInServer$Companion.start(BuiltInServer.kt:58)
        at com.intellij.idea.SocketLock.lambda$lockAndTryActivate$2(SocketLock.java:152)
        at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1700)
        ... 6 more Caused by: io.netty.channel.ChannelException: failed to open a new selector
        at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:178)
        at io.netty.channel.nio.NioEventLoop.<init>(NioEventLoop.java:145)
        at io.netty.channel.nio.NioEventLoopGroup.newChild(NioEventLoopGroup.java:183)
        at io.netty.channel.nio.NioEventLoopGroup.newChild(NioEventLoopGroup.java:38)
        at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:84)
        ... 16 more Caused by: java.io.IOException: Unable to establish loopback connection
        at java.base/sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:94)
        at java.base/sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:61)
        at java.base/java.security.AccessController.doPrivileged(Native Method)
        at java.base/sun.nio.ch.PipeImpl.<init>(PipeImpl.java:171)
        at java.base/sun.nio.ch.SelectorProviderImpl.openPipe(SelectorProviderImpl.java:50)
        at java.base/java.nio.channels.Pipe.open(Pipe.java:155)
        at java.base/sun.nio.ch.WindowsSelectorImpl.<init>(WindowsSelectorImpl.java:142)
        at java.base/sun.nio.ch.WindowsSelectorProvider.openSelector(WindowsSelectorProvider.java:44)
        at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:176)
        ... 20 more Caused by: java.net.BindException: Cannot assign requested address: connect
        at java.base/sun.nio.ch.Net.connect0(Native Method)
        at java.base/sun.nio.ch.Net.connect(Net.java:476)
        at java.base/sun.nio.ch.Net.connect(Net.java:468)
        at java.base/sun.nio.ch.SocketChannelImpl.connect(SocketChannelImpl.java:692)
        at java.base/java.nio.channels.SocketChannel.open(SocketChannel.java:194)
        at java.base/sun.nio.ch.PipeImpl$Initializer$LoopbackConnector.run(PipeImpl.java:127)
        at java.base/sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:76)
        ... 28 more 2022-01-28 11:43:56,734 [   1424]  ERROR - llij.ide.plugins.PluginManager - IntelliJ IDEA 2021.3.2  Build
#IU-213.6777.52 2022-01-28 11:43:56,745 [   1435]  ERROR - llij.ide.plugins.PluginManager - JDK: 11.0.13; VM: OpenJDK 64-Bit
Server VM; Vendor: JetBrains s.r.o. 2022-01-28 11:43:56,745 [   1435] 
ERROR - llij.ide.plugins.PluginManager - OS: Windows 10 2022-01-28
11:43:56,746 [   1436]  ERROR - llij.ide.plugins.PluginManager - Last
Action:

【问题讨论】：

标签： java intellij-idea

【解决方案1】：

有关更多详细信息和解决方法，请参阅the related issue。

这通常是由被阻止的端口、VPN 或错误配置的防火墙导致的，它阻止了本地主机连接。

常见的解决方法：

netsh int ipv4 set dynamicport tcp start=49152 num=16383
netsh int ipv4 set dynamicport udp start=49152 num=16383

net stop winnat
net start winnat

netsh winsock reset

【讨论】：