http://modemtweaks.com/unlock-idea-netsetter-e303d/
Here is the simplest Tutorial for Unlocking Idea Netsetter E303D with a simple trick. There are numerous of methods and tutorials scattered to Unlock Idea Netsetter E303D with Huawei Firmware patcher.
Just follow the below tutorial on the link below and download Huawei Firmware patcher, (Read the steps properly before implementing)
http://modemtweaks.com/unlock-idea-netsetter-e303d/