Client Version: 2025.9.1
java.lang.IllegalStateException: Unable to write active mods to game.prefs file
at com.faforever.client.mod.ModService.overrideActivatedMods(ModService.java:363)
Suppressed: The stacktrace has been enhanced by Reactor, refer to additional information below:
Assembly trace from producer [reactor.core.publisher.MonoPeekFuseable] :
reactor.core.publisher.Mono.doOnNext
com.faforever.client.mod.ModService.updateAndActivateModVersions(ModService.java:397)
Error has been observed at the following site(s):
*__Mono.doOnNext ⇢ at com.faforever.client.mod.ModService.updateAndActivateModVersions(ModService.java:397)
Original Stack Trace:
at com.faforever.client.mod.ModService.overrideActivatedMods(ModService.java:363)
at reactor.core.publisher.FluxPeekFuseable$PeekFuseableSubscriber.onNext(FluxPeekFuseable.java:196)
at reactor.core.publisher.Operators$BaseFluxToMonoOperator.completePossiblyEmpty(Operators.java:2096)
at reactor.core.publisher.MonoCollectList$MonoCollectListSubscriber.onComplete(MonoCollectList.java:118)
at reactor.core.publisher.FluxConcatIterable$ConcatIterableSubscriber.onComplete(FluxConcatIterable.java:121)
at reactor.core.publisher.FluxDefaultIfEmpty$DefaultIfEmptySubscriber.onComplete(FluxDefaultIfEmpty.java:139)
at reactor.core.publisher.FluxOnErrorReturn$ReturnSubscriber.onComplete(FluxOnErrorReturn.java:169)
at reactor.core.publisher.MonoPeekTerminal$MonoTerminalPeekSubscriber.onComplete(MonoPeekTerminal.java:299)
at reactor.core.publisher.MonoFlatMap$FlatMapMain.secondComplete(MonoFlatMap.java:246)
at reactor.core.publisher.MonoFlatMap$FlatMapInner.onNext(MonoFlatMap.java:305)
at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.complete(MonoIgnoreThen.java:294)
at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.onNext(MonoIgnoreThen.java:188)
at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.subscribeNext(MonoIgnoreThen.java:237)
at reactor.core.publisher.MonoIgnoreThen.subscribe(MonoIgnoreThen.java:51)
at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:76)
at reactor.core.publisher.MonoFlatMap$FlatMapMain.onNext(MonoFlatMap.java:165)
at reactor.core.publisher.FluxFilterFuseable$FilterFuseableSubscriber.onNext(FluxFilterFuseable.java:118)
at reactor.core.publisher.FluxMapFuseable$MapFuseableConditionalSubscriber.onNext(FluxMapFuseable.java:299)
at reactor.core.publisher.MonoNext$NextSubscriber.onNext(MonoNext.java:82)
at reactor.core.publisher.FluxPeekFuseable$PeekFuseableSubscriber.onNext(FluxPeekFuseable.java:210)
at reactor.core.publisher.FluxReplay$UnboundedReplayBuffer.replayNormal(FluxReplay.java:618)
at reactor.core.publisher.FluxReplay$UnboundedReplayBuffer.replay(FluxReplay.java:709)
at reactor.core.publisher.FluxReplay$ReplaySubscriber.onNext(FluxReplay.java:1345)
at reactor.core.publisher.FluxPeekFuseable$PeekFuseableSubscriber.onNext(FluxPeekFuseable.java:210)
at reactor.core.publisher.SerializedSubscriber.onNext(SerializedSubscriber.java:99)
at reactor.core.publisher.FluxRetryWhen$RetryWhenMainSubscriber.onNext(FluxRetryWhen.java:178)
at reactor.core.publisher.MonoFlatMapMany$FlatMapManyInner.onNext(MonoFlatMapMany.java:251)
at reactor.core.publisher.FluxOnErrorResume$ResumeSubscriber.onNext(FluxOnErrorResume.java:79)
at reactor.core.publisher.MonoFlatMapMany$FlatMapManyInner.onNext(MonoFlatMapMany.java:251)
at reactor.core.publisher.FluxIterable$IterableSubscription.slowPath(FluxIterable.java:335)
at reactor.core.publisher.FluxIterable$IterableSubscription.request(FluxIterable.java:294)
at reactor.core.publisher.MonoFlatMapMany$FlatMapManyMain.onSubscribeInner(MonoFlatMapMany.java:150)
at reactor.core.publisher.MonoFlatMapMany$FlatMapManyInner.onSubscribe(MonoFlatMapMany.java:246)
at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:201)
at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:83)
at reactor.core.publisher.Flux.subscribe(Flux.java:8891)
at reactor.core.publisher.MonoFlatMapMany$FlatMapManyMain.onNext(MonoFlatMapMany.java:196)
at reactor.core.publisher.MonoFlatMap$FlatMapMain.onNext(MonoFlatMap.java:158)
at reactor.core.publisher.MonoReduce$ReduceSubscriber.onComplete(MonoReduce.java:197)
at reactor.core.publisher.FluxMapFuseable$MapFuseableSubscriber.onComplete(FluxMapFuseable.java:152)
at reactor.core.publisher.FluxMapFuseable$MapFuseableSubscriber.onComplete(FluxMapFuseable.java:152)
at reactor.core.publisher.FluxPeekFuseable$PeekFuseableSubscriber.onComplete(FluxPeekFuseable.java:277)
at reactor.core.publisher.FluxMapFuseable$MapFuseableSubscriber.onComplete(FluxMapFuseable.java:152)
at reactor.netty.channel.FluxReceive.onInboundComplete(FluxReceive.java:413)
at reactor.netty.channel.ChannelOperations.onInboundComplete(ChannelOperations.java:455)
at reactor.netty.channel.ChannelOperations.terminate(ChannelOperations.java:509)
at reactor.netty.http.client.HttpClientOperations.onInboundNext(HttpClientOperations.java:821)
at reactor.netty.channel.ChannelOperationsHandler.channelRead(ChannelOperationsHandler.java:115)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:444)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:412)
at io.netty.channel.CombinedChannelDuplexHandler$DelegatingChannelHandlerContext.fireChannelRead(CombinedChannelDuplexHandler.java:436)
at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:346)
at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:318)
at io.netty.channel.CombinedChannelDuplexHandler.channelRead(CombinedChannelDuplexHandler.java:251)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:442)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:412)
at io.netty.handler.ssl.SslHandler.unwrap(SslHandler.java:1519)
at io.netty.handler.ssl.SslHandler.decodeJdkCompatible(SslHandler.java:1377)
at io.netty.handler.ssl.SslHandler.decode(SslHandler.java:1428)
at io.netty.handler.codec.ByteToMessageDecoder.decodeRemovalReentryProtection(ByteToMessageDecoder.java:530)
at io.netty.handler.codec.ByteToMessageDecoder.callDecode(ByteToMessageDecoder.java:469)
at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:290)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:444)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:412)
at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1357)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:440)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420)
at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:868)
at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:166)
at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:796)
at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:732)
at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:658)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:562)
at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:998)
at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
at java.base/java.lang.Thread.run(Thread.java:1583)

-Read only tag is off for game,prefs, yet in the appdata folder its called "Game.prefs", and not "game.prefs" as the error refers to