In Windows Azure SDK 1.5 the packages are no longer encrypted since they are always transferred between the development machine and Windows Azure Portal over https.
Up to Windows Azure SDK 1.4 when you generate Service Package (CSPKG) file then file was encrypted using a certificate included Windows Azure SDK. There used to be environment variable flag which can be set as TRUE to disable encryption as below:
For those who wants to see the contents of their Windows Azure Application package (Unpacking CSPKG) they can try the following:
Step 1: Copy/rename CSPKG file to ZIP file
Step 2: Inside ZIP file you will see another CSSX file as below, take it out from ZIP file.
Step 3: Renaming CSSX file to ZIP file, and unzipping it will give you all the contents in your package