I was trying to upload the app store build zip file of my app to app store.
When using behind my office firewall, the TCP/IP connection failed.
I need to k
in my case the problem was related to Java (Application Loader uses Java, and Java does not inherit the Mac's proxy settings). I had to set the proxy settings to Java.
If you are on a Mac OS pre-10.7.5 (more or less) just look for the Java Preferences application via the spotlight. If not, this SO question specifies another way of doing so.