I downloaded the Suite for the phone, the Google USB drivers and the Phone's connection drivers. So far, the phone works perfectly with the PC but Eclipse still refuses to see the phone and Device Manager is convincing me that I have no hardware compatible with the Google USB drivers. Therefore the Google USB drivers are downloaded but not installed or assigned to any device. I followed every answer on stackoverflow that there is so far, but none have solved the problem.
And last verify that adb.exe can detect you device from cmd (if running in windows) ..(path to your SDK)\platform-tools\adb device
If last step fails, then re-install you device driver, it should be handled automatically by sony pc-companion for your xperia phone.