YES YES YES,
Today, I installed a regular update on MAC side and they released a new Thunderbold Firmware!!!!
I tested the behavior with two data projectors ... AND YES - IT WORKS.
Honestly I will switch to a Fujitsu laptop this week, because I really need a solid and reliable system for day-to-day work. Month of waiting for a fix really were extremely frustrating! However, I now can sell it with a good feeling. By By MAC, I tried but it did not work out
It seems last update for NVIDIA driver in Windows 7 bootcamp solved my issue.
I had tried with two Acer projectors which were before not possible to increase resolution bigger than 640*480 are now giving me the option of 1280*1024 (which is enough for me to make presentations).
Please try and see in your MBP's..
Thanks to everyone..
I just want to confirm Ergin's information. After updating the GeForce driver from version 296.10 (release date: 2012-03-13) to the latest version (320.49 from 2013-07-01), connecting to external projectors went fine - again. When I started using my MBP with bootcamp and Windows 7, I never experienced any problem at all when connecting to external projectors. The first time I did was in fall 2012, most probably after installing a newer but faulty version of the GeForce driver. I hope it will work again with other projectors, too. If not, I'm going to return to this thread.
To fix the external monitor resolution by showing more sensible resolution options for this monitor (including the correct 2560x1600-pixel resolution), hold the Option key while clicking on the Scaled radio button.