Error while compiling app

[Braalfa]

The Gradle Console displays this after trying to compile:

Error:Execution failed for task ':senzc:processReleaseResources'.

com.android.ide.common.process.ProcessException: org.gradle.process.internal.ExecException: Process 'command 'C:\Users\Usuario\AppData\Local\Android\sdk1\build-tools\21.0.0\aapt.exe'' finished with non-zero exit value

Solution:
Change this in build.gradle(Module senz)
buildToolsVersion "21.1.2"

And change this in build.gradle(Module app)
buildToolsVersion "21.1.2"