Intellij Idea fails to start with VPN enabled

I am having a trouble with launching Intellij Idea Ultimate Edition 2021.1.2 (also tried 2020.3.1) with VPN enabled (I am using GlobalProtect) on Windows 10. I’ve been working on this setup for quite a long time, but recently something went wrong with no obvious changes made. So, after launching Intellij Idea I get an error window with following:

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$AsyncSupply.run(CompletableFuture.java:1702)
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
    at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1$1.run(Executors.java:668)
    at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1$1.run(Executors.java:665)
    at java.base/java.security.AccessController.doPrivileged(Native Method)
    at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1.run(Executors.java:665)
    at java.base/java.lang.Thread.run(Thread.java:829)
Caused by: java.lang.IllegalStateException: failed to create a child event loop
    at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:88)
    at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:58)
    at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:47)
    at io.netty.channel.MultithreadEventLoopGroup.<init>(MultithreadEventLoopGroup.java:59)
    at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:86)
    at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:81)
    at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:68)
    at org.jetbrains.io.BuiltInServerKt.multiThreadEventLoopGroup(BuiltInServer.kt:144)
    at org.jetbrains.io.BuiltInServerKt.access$multiThreadEventLoopGroup(BuiltInServer.kt:1)
    at org.jetbrains.io.BuiltInServer$Companion.start(BuiltInServer.kt:54)
    at org.jetbrains.io.BuiltInServer.start(BuiltInServer.kt)
    at com.intellij.idea.SocketLock.lambda$lockAndTryActivate$2(SocketLock.java:171)
    at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1700)
    ... 7 more
Caused by: io.netty.channel.ChannelException: failed to open a new selector
    at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:175)
    at io.netty.channel.nio.NioEventLoop.<init>(NioEventLoop.java:142)
    at io.netty.channel.nio.NioEventLoopGroup.newChild(NioEventLoopGroup.java:146)
    at io.netty.channel.nio.NioEventLoopGroup.newChild(NioEventLoopGroup.java:37)
    at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:84)
    ... 19 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:173)
    ... 23 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)
    ... 31 more

-----
Your JRE: 11.0.11+9-b1341.57 amd64 (JetBrains s.r.o.)
C:Program FilesJetBrainsIntelliJ IDEA 2021.1.2jbr

After I prees OK button IDE shuts down. If I disable VPN everything works fine. After some research I found the way to start Idea with VPN enabled with VM option -Djava.net.preferIPv4Stack=true, but that really doesn’t solve the problem, because I still need VPN for my project. If I start Idea and then enable VPN, after I try to start project I get Cannot assign requested address: no further information message from Gradle. Or if I simply open Maven project, I get

org.jetbrains.idea.maven.server.CannotStartServerException: java.util.concurrent.ExecutionException: java.rmi.ConnectException: Connection refused to host: 127.0.0.1; nested exception is: 
    java.net.ConnectException: connect: Address is invalid on local machine, or port is not valid on remote machine
    at org.jetbrains.idea.maven.server.MavenServerConnectorImpl.getServer(MavenServerConnectorImpl.java:100)
    at org.jetbrains.idea.maven.server.MavenServerConnector.lambda$applyProfiles$3(MavenServerConnector.java:85)
    at org.jetbrains.idea.maven.server.MavenServerConnectorImpl.perform(MavenServerConnectorImpl.java:169)
    at org.jetbrains.idea.maven.server.MavenServerConnector.applyProfiles(MavenServerConnector.java:84)
    at org.jetbrains.idea.maven.project.MavenProjectReader.applyProfiles(MavenProjectReader.java:422)
    at org.jetbrains.idea.maven.project.MavenProjectReader.doReadProjectModel(MavenProjectReader.java:98)
    at org.jetbrains.idea.maven.project.MavenProjectReader$1.doProcessParent(MavenProjectReader.java:479)
    at org.jetbrains.idea.maven.project.MavenProjectReader$1.doProcessParent(MavenProjectReader.java:455)
    at org.jetbrains.idea.maven.project.MavenParentProjectFileProcessor.processRepositoryParent(MavenParentProjectFileProcessor.java:84)
    at org.jetbrains.idea.maven.project.MavenParentProjectFileProcessor.process(MavenParentProjectFileProcessor.java:62)
    at org.jetbrains.idea.maven.project.MavenProjectReader.resolveInheritance(MavenProjectReader.java:482)
    at org.jetbrains.idea.maven.project.MavenProjectReader.doReadProjectModel(MavenProjectReader.java:95)
    at org.jetbrains.idea.maven.project.MavenProjectReader$1.doProcessParent(MavenProjectReader.java:479)
    at org.jetbrains.idea.maven.project.MavenProjectReader$1.doProcessParent(MavenProjectReader.java:455)
    at org.jetbrains.idea.maven.project.MavenParentProjectFileProcessor.processRepositoryParent(MavenParentProjectFileProcessor.java:84)
    at org.jetbrains.idea.maven.project.MavenParentProjectFileProcessor.process(MavenParentProjectFileProcessor.java:62)
    at org.jetbrains.idea.maven.project.MavenProjectReader.resolveInheritance(MavenProjectReader.java:482)
    at org.jetbrains.idea.maven.project.MavenProjectReader.doReadProjectModel(MavenProjectReader.java:95)
    at org.jetbrains.idea.maven.project.MavenProjectReader.readProject(MavenProjectReader.java:56)
    at org.jetbrains.idea.maven.project.MavenProject.read(MavenProject.java:683)
    at org.jetbrains.idea.maven.project.MavenProjectsTree.doUpdate(MavenProjectsTree.java:549)
    at org.jetbrains.idea.maven.project.MavenProjectsTree.update(MavenProjectsTree.java:459)
    at org.jetbrains.idea.maven.project.MavenProjectsTree.updateAll(MavenProjectsTree.java:427)
    at org.jetbrains.idea.maven.project.MavenProjectsProcessorReadingTask.perform(MavenProjectsProcessorReadingTask.java:61)
    at org.jetbrains.idea.maven.project.MavenProjectsProcessor.doProcessPendingTasks(MavenProjectsProcessor.java:146)
    at org.jetbrains.idea.maven.project.MavenProjectsProcessor$1.run(MavenProjectsProcessor.java:115)
    at org.jetbrains.idea.maven.utils.MavenUtil.lambda$runInBackground$6(MavenUtil.java:536)
    at com.intellij.util.RunnableCallable.call(RunnableCallable.java:20)
    at com.intellij.util.RunnableCallable.call(RunnableCallable.java:11)
    at com.intellij.openapi.application.impl.ApplicationImpl$1.call(ApplicationImpl.java:265)
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
    at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1$1.run(Executors.java:668)
    at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1$1.run(Executors.java:665)
    at java.base/java.security.AccessController.doPrivileged(Native Method)
    at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1.run(Executors.java:665)
    at java.base/java.lang.Thread.run(Thread.java:829)
Caused by: java.util.concurrent.ExecutionException: java.rmi.ConnectException: Connection refused to host: 127.0.0.1; nested exception is: 
    java.net.ConnectException: connect: Address is invalid on local machine, or port is not valid on remote machine
    at java.base/java.util.concurrent.CompletableFuture.reportGet(CompletableFuture.java:395)
    at java.base/java.util.concurrent.CompletableFuture.get(CompletableFuture.java:1999)
    at org.jetbrains.concurrency.AsyncPromise.get(AsyncPromise.kt:42)
    at org.jetbrains.idea.maven.server.MavenServerConnectorImpl.waitForServer(MavenServerConnectorImpl.java:117)
    at org.jetbrains.idea.maven.server.MavenServerConnectorImpl.getServer(MavenServerConnectorImpl.java:83)
    ... 37 more
Caused by: java.rmi.ConnectException: Connection refused to host: 127.0.0.1; nested exception is: 
    java.net.ConnectException: connect: Address is invalid on local machine, or port is not valid on remote machine
    at java.rmi/sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:623)
    at java.rmi/sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:209)
    at java.rmi/sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:196)
    at java.rmi/sun.rmi.server.UnicastRef.newCall(UnicastRef.java:343)
    at java.rmi/sun.rmi.registry.RegistryImpl_Stub.lookup(RegistryImpl_Stub.java:116)
    at com.intellij.execution.rmi.RemoteProcessSupport.lambda$acquire$2(RemoteProcessSupport.java:316)
    at com.intellij.openapi.util.ClassLoaderUtil.computeWithClassLoader(ClassLoaderUtil.java:31)
    at com.intellij.execution.rmi.RemoteUtil.executeWithClassLoader(RemoteUtil.java:202)
    at com.intellij.execution.rmi.RemoteProcessSupport.acquire(RemoteProcessSupport.java:314)
    at com.intellij.execution.rmi.RemoteProcessSupport.acquire(RemoteProcessSupport.java:188)
    at org.jetbrains.idea.maven.server.MavenServerConnectorImpl$StartServerTask.run(MavenServerConnectorImpl.java:247)
    ... 11 more
Caused by: java.net.ConnectException: connect: Address is invalid on local machine, or port is not valid on remote machine
    at java.base/java.net.PlainSocketImpl.connect0(Native Method)
    at java.base/java.net.PlainSocketImpl.socketConnect(PlainSocketImpl.java:101)
    at java.base/java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:399)
    at java.base/java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:242)
    at java.base/java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:224)
    at java.base/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
    at java.base/java.net.Socket.connect(Socket.java:609)
    at java.base/java.net.Socket.connect(Socket.java:558)
    at java.base/java.net.Socket.<init>(Socket.java:454)
    at java.base/java.net.Socket.<init>(Socket.java:231)
    at com.intellij.execution.rmi.RemoteServer$1.createSocket(RemoteServer.java:174)
    at java.rmi/sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:617)
    ... 21 more

Any ideas on how to resolve this issue?

Answer

Adding system variable _JAVA_OPTIONS:-Djava.net.preferIPv4Stack=true resolved all issues