Android is not working on Windows 7

I am novice in android development and facing some problems. I have installed Eclipse helios along with ADT 0.9.9 and Android Windows SDK and android 2.2 package. I have developed a small app for testing (one button and EditText control which displays message when user clicks button), it complied successfully. But when I want to run this on emulator it开发者_StackOverflows not showing there. It once installed and worked but after I updated my code (Updated only message which will be displayed when user clicks button) its not showing the updated output so I uninstalled app from emulator using app manager. I tried every thing (used Run As and creating Android config even freshly installed SDK) to solve the problem but couldn't. Even DDMS not listing any process or any sign of running emulator. Not in even Log Cat

1. In bin folder of application project you will find the .apk file. Manually install it on emulator or device
2. Check manifest file to see which activity is first loaded?

I prefer 2.