Extension Name space is invalid.

I am using flashbuilder 4.7 with AIR SDK 15.0 on adding ANE i got following error.

Process terminated unexpectedly.

The content cannot be loaded because there was a problem loading an extension: Error: Extension namespace is invalid for C:\Users\New\Adobe Flash Builder 4.7\.metadata\.plugins\com.adobe.flexbuilder.project.ui\ANEFiles\SampleTest\win32\sampleO utput.ane

I have ensured Extension Id are same in Extension.xml and discripter file.