Unable to resolve project target 'android-19'

Configuring
(2,113.92 ms)
Parsing source code
(3,523.88 ms)
Compiling syntax tree
(12,430.20 ms)
Generating code and data
(20,800.88 ms)
Building native target
1/2: libHello.so
2/2: Hello-debug.apk
BUILD FAILED
C:\Users\Administrator\AppData\Local\Android\sdk\tools\ant\build.xml:538: Unable to resolve project target 'android-19'
Total time: 1 second
(unknown): E0000: Native build failed
(7,510.74 ms)
Build completed in 46.39 seconds.
    0 Warning(s)
    1 Error(s)
Error Summary
(unknown): E0000: Native build failed
Build complete.

This is what caused the problem?

Hi, as I responded in your last thread.

You are missing android platform 19 (Unable to resolve project target ‘android-19’). So try to run this command here C:\Users\Administrator\AppData\Local\Android\sdk\tools\android update sdk -s -u -a -t platform-tools,build-tools-23.0.2,android-19,android-21

Thank you, I solve the