The BlackBerry OS v126.96.36.1990 was made by BlackBerry (RIM) and released by Sprint, but it will run on any 9650. Often, just wiping and loading the phone with the original software fixes a lot of problems.
Originally Posted by m02ndk
OSBB 600v6 is a hybrid OS. If you don't know what "hybrid OS" means, it is a collection of various BlackBerry OS files from different versions of the OS designed for different BlackBerry handsets. For example, this v6 hybrid contains parts of the OS188.8.131.520 released for the 9650, parts of the .650 released for the 9780, and parts of the 184.108.40.2067 for the Torch 9810. Many of the OS files are interchangeable from one BlackBerry to the next, and the goal is to make a combination of files that work well together. The goal might be to make the OS run a little smoother, to make the battery life a bit better, or to make the browser work faster. Often, however, a hybrid will fix a particular issue at the expense of creating another.
Your original post is lacking detail. Did you just buy the phone? Was it working at one time, and recently stopped working? Where are you trying to use it (what part of the country)? You did not describe any of your "many issues", so nobody here will be able to help you further without more information. There are many folks here that will help however they can. The more info you deliver, the more help you're likely to get.