Why can't I generate a signed APK?

I have an app, that works just the way I want it to and in the past I was able to generate signed APKs.
However now in my newest version (1.11) I can't build a signed akp anymore. This thing gets shown to me:

Executing tasks: [:app:assembleRelease] in project C:\Users\Gereon\AndroidStudioProjects\Akkubuch
> Task :app:preBuild UP-TO-DATE
> Task :app:preReleaseBuild UP-TO-DATE
> Task :app:compileReleaseAidl NO-SOURCE
> Task :app:generateReleaseBuildConfig UP-TO-DATE
> Task :app:compileReleaseRenderscript NO-SOURCE
> Task :app:javaPreCompileRelease UP-TO-DATE
> Task :app:mainApkListPersistenceRelease
> Task :app:generateReleaseResValues UP-TO-DATE
> Task :app:generateReleaseResources UP-TO-DATE
> Task :app:mergeReleaseResources UP-TO-DATE
> Task :app:createReleaseCompatibleScreenManifests
> Task :app:extractDeepLinksRelease UP-TO-DATE
> Task :app:processReleaseManifest
> Task :app:processReleaseResources
> Task :app:compileReleaseJavaWithJavac UP-TO-DATE
> Task :app:compileReleaseSources UP-TO-DATE
> Task :app:prepareLintJar UP-TO-DATE
> Task :app:lintVitalRelease FAILED
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':app:lintVitalRelease'.
> Lint infrastructure error
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.android.tools.lint.gradle.api.ReflectiveLintRunner.runLint(ReflectiveLintRunner.kt:38)
at com.android.build.gradle.tasks.LintBaseTask.runLint(LintBaseTask.java:114)
at com.android.build.gradle.tasks.LintPerVariantTask.lint(LintPerVariantTask.java:63)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:103)
at org.gradle.api.internal.project.taskfactory.StandardTaskAction.doExecute(StandardTaskAction.java:49)
at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:42)
at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:28)
at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:717)
at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:684)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$5.run(ExecuteActionsTaskExecuter.java:476)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:402)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:394)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$1.execute(DefaultBuildOperationExecutor.java:165)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:250)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:158)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:92)
at org.gradle.internal.operations.DelegatingBuildOperationExecutor.run(DelegatingBuildOperationExecutor.java:31)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:461)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:444)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.access$200(ExecuteActionsTaskExecuter.java:93)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$TaskExecution.execute(ExecuteActionsTaskExecuter.java:237)
at org.gradle.internal.execution.steps.ExecuteStep.lambda$execute$1(ExecuteStep.java:33)
at java.util.Optional.orElseGet(Optional.java:267)
at org.gradle.internal.execution.steps.ExecuteStep.execute(ExecuteStep.java:33)
at org.gradle.internal.execution.steps.ExecuteStep.execute(ExecuteStep.java:26)
at org.gradle.internal.execution.steps.CleanupOutputsStep.execute(CleanupOutputsStep.java:58)
at org.gradle.internal.execution.steps.CleanupOutputsStep.execute(CleanupOutputsStep.java:35)
at org.gradle.internal.execution.steps.ResolveInputChangesStep.execute(ResolveInputChangesStep.java:48)
at org.gradle.internal.execution.steps.ResolveInputChangesStep.execute(ResolveInputChangesStep.java:33)
at org.gradle.internal.execution.steps.CancelExecutionStep.execute(CancelExecutionStep.java:39)
at org.gradle.internal.execution.steps.TimeoutStep.executeWithoutTimeout(TimeoutStep.java:73)
at org.gradle.internal.execution.steps.TimeoutStep.execute(TimeoutStep.java:54)
at org.gradle.internal.execution.steps.CatchExceptionStep.execute(CatchExceptionStep.java:35)
at org.gradle.internal.execution.steps.CreateOutputsStep.execute(CreateOutputsStep.java:51)
at org.gradle.internal.execution.steps.SnapshotOutputsStep.execute(SnapshotOutputsStep.java:45)
at org.gradle.internal.execution.steps.SnapshotOutputsStep.execute(SnapshotOutputsStep.java:31)
at org.gradle.internal.execution.steps.CacheStep.executeWithoutCache(CacheStep.java:208)
at org.gradle.internal.execution.steps.CacheStep.execute(CacheStep.java:70)
at org.gradle.internal.execution.steps.CacheStep.execute(CacheStep.java:45)
at org.gradle.internal.execution.steps.BroadcastChangingOutputsStep.execute(BroadcastChangingOutputsStep.java:49)
at org.gradle.internal.execution.steps.StoreSnapshotsStep.execute(StoreSnapshotsStep.java:43)
at org.gradle.internal.execution.steps.StoreSnapshotsStep.execute(StoreSnapshotsStep.java:32)
at org.gradle.internal.execution.steps.RecordOutputsStep.execute(RecordOutputsStep.java:38)
at org.gradle.internal.execution.steps.RecordOutputsStep.execute(RecordOutputsStep.java:24)
at org.gradle.internal.execution.steps.SkipUpToDateStep.executeBecause(SkipUpToDateStep.java:96)
at org.gradle.internal.execution.steps.SkipUpToDateStep.lambda$execute$0(SkipUpToDateStep.java:89)
at java.util.Optional.map(Optional.java:215)
at org.gradle.internal.execution.steps.SkipUpToDateStep.execute(SkipUpToDateStep.java:54)
at org.gradle.internal.execution.steps.SkipUpToDateStep.execute(SkipUpToDateStep.java:38)
at org.gradle.internal.execution.steps.ResolveChangesStep.execute(ResolveChangesStep.java:76)
at org.gradle.internal.execution.steps.ResolveChangesStep.execute(ResolveChangesStep.java:37)
at org.gradle.internal.execution.steps.legacy.MarkSnapshottingInputsFinishedStep.execute(MarkSnapshottingInputsFinishedStep.java:36)
at org.gradle.internal.execution.steps.legacy.MarkSnapshottingInputsFinishedStep.execute(MarkSnapshottingInputsFinishedStep.java:26)
at org.gradle.internal.execution.steps.ResolveCachingStateStep.execute(ResolveCachingStateStep.java:90)
at org.gradle.internal.execution.steps.ResolveCachingStateStep.execute(ResolveCachingStateStep.java:48)
at org.gradle.internal.execution.steps.CaptureStateBeforeExecutionStep.execute(CaptureStateBeforeExecutionStep.java:69)
at org.gradle.internal.execution.steps.CaptureStateBeforeExecutionStep.execute(CaptureStateBeforeExecutionStep.java:47)
at org.gradle.internal.execution.impl.DefaultWorkExecutor.execute(DefaultWorkExecutor.java:33)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:140)
at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:62)
at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:108)
at org.gradle.api.internal.tasks.execution.ResolveBeforeExecutionOutputsTaskExecuter.execute(ResolveBeforeExecutionOutputsTaskExecuter.java:67)
at org.gradle.api.internal.tasks.execution.ResolveAfterPreviousExecutionStateTaskExecuter.execute(ResolveAfterPreviousExecutionStateTaskExecuter.java:46)
at org.gradle.api.internal.tasks.execution.CleanupStaleOutputsExecuter.execute(CleanupStaleOutputsExecuter.java:94)
at org.gradle.api.internal.tasks.execution.FinalizePropertiesTaskExecuter.execute(FinalizePropertiesTaskExecuter.java:46)
at org.gradle.api.internal.tasks.execution.ResolveTaskExecutionModeExecuter.execute(ResolveTaskExecutionModeExecuter.java:95)
at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:57)
at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:56)
at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:36)
at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.executeTask(EventFiringTaskExecuter.java:77)
at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.call(EventFiringTaskExecuter.java:55)
at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.call(EventFiringTaskExecuter.java:52)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:416)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:406)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$1.execute(DefaultBuildOperationExecutor.java:165)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:250)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:158)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.call(DefaultBuildOperationExecutor.java:102)
at org.gradle.internal.operations.DelegatingBuildOperationExecutor.call(DelegatingBuildOperationExecutor.java:36)
at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter.execute(EventFiringTaskExecuter.java:52)
at org.gradle.execution.plan.LocalTaskNodeExecutor.execute(LocalTaskNodeExecutor.java:43)
at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:355)
at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:343)
at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:336)
at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:322)
at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker$1.execute(DefaultPlanExecutor.java:134)
at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker$1.execute(DefaultPlanExecutor.java:129)
at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.execute(DefaultPlanExecutor.java:202)
at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.executeNextNode(DefaultPlanExecutor.java:193)
at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.run(DefaultPlanExecutor.java:129)
at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:64)
at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:48)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:56)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.RuntimeException: Invalid main APK outputs : EarlySyncBuildOutput(type=com.android.build.gradle.internal.scope.InternalArtifactType$APK@78c5bc70, apkType=MAIN, filtersData=[], version=0, output=C:\Users\Gereon\AndroidStudioProjects\Akkubuch\app\release\Akkubuch - V.1.1.apk),EarlySyncBuildOutput(type=com.android.build.gradle.internal.scope.InternalArtifactType$APK@78c5bc70, apkType=MAIN, filtersData=[], version=0, output=C:\Users\Gereon\AndroidStudioProjects\Akkubuch\app\release\Akkubuch - V.1.10.apk),EarlySyncBuildOutput(type=com.android.build.gradle.internal.scope.InternalArtifactType$APK@78c5bc70, apkType=MAIN, filtersData=[], version=0, output=C:\Users\Gereon\AndroidStudioProjects\Akkubuch\app\release\Akkubuch - V.1.2.apk),EarlySyncBuildOutput(type=com.android.build.gradle.internal.scope.InternalArtifactType$APK@78c5bc70, apkType=MAIN, filtersData=[], version=0, output=C:\Users\Gereon\AndroidStudioProjects\Akkubuch\app\release\Akkubuch - V.1.3.apk),EarlySyncBuildOutput(type=com.android.build.gradle.internal.scope.InternalArtifactType$APK@78c5bc70, apkType=MAIN, filtersData=[], version=0, output=C:\Users\Gereon\AndroidStudioProjects\Akkubuch\app\release\Akkubuch - V.1.4.2.apk),EarlySyncBuildOutput(type=com.android.build.gradle.internal.scope.InternalArtifactType$APK@78c5bc70, apkType=MAIN, filtersData=[], version=0, output=C:\Users\Gereon\AndroidStudioProjects\Akkubuch\app\release\Akkubuch - V.1.4.apk),EarlySyncBuildOutput(type=com.android.build.gradle.internal.scope.InternalArtifactType$APK@78c5bc70, apkType=MAIN, filtersData=[], version=0, output=C:\Users\Gereon\AndroidStudioProjects\Akkubuch\app\release\Akkubuch - V.1.5.apk),EarlySyncBuildOutput(type=com.android.build.gradle.internal.scope.InternalArtifactType$APK@78c5bc70, apkType=MAIN, filtersData=[], version=0, output=C:\Users\Gereon\AndroidStudioProjects\Akkubuch\app\release\Akkubuch - V.1.6.2.apk),EarlySyncBuildOutput(type=com.android.build.gradle.internal.scope.InternalArtifactType$APK@78c5bc70, apkType=MAIN, filtersData=[], version=0, output=C:\Users\Gereon\AndroidStudioProjects\Akkubuch\app\release\Akkubuch - V.1.6.apk),EarlySyncBuildOutput(type=com.android.build.gradle.internal.scope.InternalArtifactType$APK@78c5bc70, apkType=MAIN, filtersData=[], version=0, output=C:\Users\Gereon\AndroidStudioProjects\Akkubuch\app\release\Akkubuch - V.1.7.2.apk),EarlySyncBuildOutput(type=com.android.build.gradle.internal.scope.InternalArtifactType$APK@78c5bc70, apkType=MAIN, filtersData=[], version=0, output=C:\Users\Gereon\AndroidStudioProjects\Akkubuch\app\release\Akkubuch - V.1.7.apk),EarlySyncBuildOutput(type=com.android.build.gradle.internal.scope.InternalArtifactType$APK@78c5bc70, apkType=MAIN, filtersData=[], version=0, output=C:\Users\Gereon\AndroidStudioProjects\Akkubuch\app\release\Akkubuch - V.1.8.apk),EarlySyncBuildOutput(type=com.android.build.gradle.internal.scope.InternalArtifactType$APK@78c5bc70, apkType=MAIN, filtersData=[], version=0, output=C:\Users\Gereon\AndroidStudioProjects\Akkubuch\app\release\Akkubuch - V.1.9.apk)
at com.android.build.gradle.internal.ide.AndroidArtifactImpl.computeBuildOutputs(AndroidArtifactImpl.java:197)
at com.android.build.gradle.internal.ide.AndroidArtifactImpl.<init>(AndroidArtifactImpl.java:137)
at com.android.build.gradle.internal.ide.ModelBuilder.createAndroidArtifact(ModelBuilder.java:960)
at com.android.build.gradle.internal.ide.ModelBuilder.createVariant(ModelBuilder.java:584)
at com.android.build.gradle.internal.ide.ModelBuilder.buildAndroidProject(ModelBuilder.java:399)
at com.android.build.gradle.internal.ide.ModelBuilder.buildAll(ModelBuilder.java:193)
at com.android.build.gradle.internal.AppModelBuilder.buildAll(AppModelBuilder.kt:63)
at org.gradle.tooling.provider.model.internal.DefaultToolingModelBuilderRegistry$BuildOperationWrappingToolingModelBuilder$1$1.create(DefaultToolingModelBuilderRegistry.java:104)
at org.gradle.api.internal.project.DefaultProjectStateRegistry.withLenientState(DefaultProjectStateRegistry.java:133)
at org.gradle.tooling.provider.model.internal.DefaultToolingModelBuilderRegistry$BuildOperationWrappingToolingModelBuilder$1.call(DefaultToolingModelBuilderRegistry.java:100)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:416)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:406)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$1.execute(DefaultBuildOperationExecutor.java:165)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:250)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:158)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.call(DefaultBuildOperationExecutor.java:102)
at org.gradle.internal.operations.DelegatingBuildOperationExecutor.call(DelegatingBuildOperationExecutor.java:36)
at org.gradle.tooling.provider.model.internal.DefaultToolingModelBuilderRegistry$BuildOperationWrappingToolingModelBuilder.buildAll(DefaultToolingModelBuilderRegistry.java:97)
at com.android.tools.lint.gradle.LintGradleExecution.createAndroidProject(LintGradleExecution.java:369)
at com.android.tools.lint.gradle.LintGradleExecution.analyze(LintGradleExecution.java:88)
... 104 more
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
* Get more help at https://help.gradle.org
BUILD FAILED in 1s
12 actionable tasks: 5 executed, 7 up-to-date

Also 3 other errors plop up:
java.lang.reflect.InvocationTargetException
java.lang.RuntimeException: Invalid main APK outputs :
Lint infrastructure error
Caused by: java.lang.reflect.InvocationTargetException

OK just had the same issue. Thought I had Lint issues to resolve, but checking App> build > reports > lint-results-release-fatal showed a clean slate.

Tried to clean, but that did not work. So I ended up deleting the 'build' and 'release' folders. Somehow that worked. Don't know what actually caused it.

I removed all content from the destiny folder and then the error disappear.

First of all you need to find the problems by performing the following actions:
Go to "Analyze" -> Inspect code. After the inspection, the errors should show up.
I've found myself some errors there. Even though it did not work after fixing the errors, I've updated Android studio and it finally solved the issue.

Doing invalidate cache and restart option as shown below fixed this issue for me