I get this error sometimes when I switch my app branches! and it solve randomly. I am not sure if it is a bug in AS or my system but I am sure my code is fine!

I also tried deleting my debug.keystore, restarting AS and system(!!!) but it didn't solved.

Here is a full log from gradle:

----------------------------------------------------------------------

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':chris-app:packageDemoDebug'.
> java.io.IOException: Failed to generate v1 signature

* Try:
Run with --info or --debug option to get more log output.

* Exception is:
org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':chris-app:packageDemoDebug'.
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:100)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:70)
at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:64)
at org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter.execute(ResolveTaskOutputCachingStateExecuter.java:54)
at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:58)
at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:88)
at org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter.execute(ResolveTaskArtifactStateTaskExecuter.java:52)
at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:52)
at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:54)
at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:34)
at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker$1.run(DefaultTaskGraphExecuter.java:243)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:197)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:107)
at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:236)
at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:225)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.processTask(DefaultTaskPlanExecutor.java:124)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.access$200(DefaultTaskPlanExecutor.java:80)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:105)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:99)
at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.execute(DefaultTaskExecutionPlan.java:625)
at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.executeWithTask(DefaultTaskExecutionPlan.java:580)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.run(DefaultTaskPlanExecutor.java:99)
at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
Caused by: org.gradle.tooling.BuildException: java.io.IOException: Failed to generate v1 signature
at com.android.build.gradle.internal.scope.OutputScope.lambda$parallelForEachOutput$10(OutputScope.java:240)
at com.android.build.gradle.internal.scope.OutputScope.parallelForEachOutput(OutputScope.java:235)
at com.android.build.gradle.internal.scope.OutputScope.parallelForEachOutput(OutputScope.java:196)
at com.android.build.gradle.internal.scope.OutputScope.parallelForEachOutput(OutputScope.java:180)
at com.android.build.gradle.tasks.PackageAndroidArtifact.doFullTaskAction(PackageAndroidArtifact.java:466)
at com.android.build.gradle.internal.tasks.IncrementalTask.taskAction(IncrementalTask.java:80)
at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:73)
at org.gradle.api.internal.project.taskfactory.DefaultTaskClassInfoStore$IncrementalTaskAction.doExecute(DefaultTaskClassInfoStore.java:168)
at org.gradle.api.internal.project.taskfactory.DefaultTaskClassInfoStore$StandardTaskAction.execute(DefaultTaskClassInfoStore.java:134)
at org.gradle.api.internal.project.taskfactory.DefaultTaskClassInfoStore$StandardTaskAction.execute(DefaultTaskClassInfoStore.java:121)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$1.run(ExecuteActionsTaskExecuter.java:122)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:197)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:107)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:111)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:92)
... 27 more
Caused by: java.lang.RuntimeException: java.io.IOException: Failed to generate v1 signature
Caused by: java.io.IOException: Failed to generate v1 signature
at com.android.apkzlib.sign.SigningExtension.onOutputZipReadyForUpdate(SigningExtension.java:297)
at com.android.apkzlib.sign.SigningExtension.access$200(SigningExtension.java:55)
at com.android.apkzlib.sign.SigningExtension$1.lambda$beforeUpdate$2(SigningExtension.java:175)
at com.android.apkzlib.zip.ZFile.notify(ZFile.java:2099)
at com.android.apkzlib.zip.ZFile.update(ZFile.java:871)
at com.android.apkzlib.zip.ZFile.close(ZFile.java:1161)
at com.android.apkzlib.zfile.ApkZFileCreator.close(ApkZFileCreator.java:172)
at com.google.common.io.Closer.close(Closer.java:216)
at com.android.builder.internal.packaging.IncrementalPackager.close(IncrementalPackager.java:332)
at com.android.build.gradle.tasks.PackageAndroidArtifact.doTask(PackageAndroidArtifact.java:698)
at com.android.build.gradle.tasks.PackageAndroidArtifact.splitFullAction(PackageAndroidArtifact.java:520)
at com.android.build.gradle.internal.scope.OutputScope.lambda$parallelForEachOutput$6(OutputScope.java:185)
at com.android.build.gradle.internal.scope.OutputScope.lambda$parallelForEachOutput$7(OutputScope.java:202)
at com.android.build.gradle.internal.scope.OutputScope.lambda$null$8(OutputScope.java:224)
"
at com.android.apksig.internal.apk.v1.V1SchemeSigner.checkEntryNameValid(V1SchemeSigner.java:406)
at com.android.apksig.internal.apk.v1.V1SchemeSigner.generateManifestFile(V1SchemeSigner.java:373)
at com.android.apksig.internal.apk.v1.V1SchemeSigner.sign(V1SchemeSigner.java:253)
at com.android.apksig.DefaultApkSignerEngine.outputJarEntries(DefaultApkSignerEngine.java:372)
at com.android.apkzlib.sign.SigningExtension.onOutputZipReadyForUpdate(SigningExtension.java:295)
... 13 more

BUILD FAILED in 2m 49s

------------------------------------------------------------

Build: 3.0 Canary 7, AI-171.4182969, 201707142150,

AI-171.4182969, JRE 1.8.0_152-release-884-b01x64 JetBrains s.r.o, OS Mac OS X(x86_64) v10.12.6 unknown, screens 1920x1080, 1280x800; Retina

IMPORTANT: Please read https://developer.android.com/studio/report-bugs.html carefully and supply all required information.