I definitely feel your pain. I went through the uninstall/reinstall ritual repeatedly after installing DPI 14. I also asked Nuance support for help, but they were unable to identify the problem, even after working on it for months. After 6 months of trying anything and everything, I found out it was an intermittently defective microphone. (I discovered this by setting the microphone so that I could hear myself dictating.) Once I got a replacement from the manufacturer my problem with Dragon was solved.
There are just so many possibilities for what could go wrong, it is a bit overwhelming ...
As far as shutting down Dragon, people on the KnowBrainer forums also talk about the fact that the Dragon processes quite often fail to terminate when you "Exit" Dragon.
When I want to shut down Dragon, I now generally try to close my profile first. There is so much talk in the KnowBrainer forums about damage to profiles that I just want to avoid all possibility of damaging my profile if I cannot terminate the program properly. After closing the profile, I watch the Windows Task Manager ("Processes" tab, sorted by "Description" to gather the Dragon processes together), and wait for the memory size of the "natspeak.exe" process to drop from half a gigabyte to around 70 to 90 megabytes. Note that if Studio is running, Dragon sometimes refuses to close the profile until I terminate Studio. (Also note that the Studio process can hang around in the background for a while before terminating, so I watch in Windows Task Manager to make sure the Studio process ends.)
Once the profile is closed, I try to exit Dragon. Quite often, however, the Dragon processes simply do not terminate. I wait a while and then manually end the "natspeak.exe" process using the "End Process" button in Windows Task Manager. Usually this also closes the "dgnuiasvr" process after a short period. If it does not, then I manually terminate this process, too.
Needless to say, during those 6 months I was looking for the problem I also repeatedly created new profiles. The intermittently defective microphone led to cumulative problems with the profile, causing performance to deteriorate.
But Dragon runs so well now that I probably only exit the program once a week. I just turn the microphone off and let it run in the background until I need it again.
I do, however, rarely dictate directly into Studio. It is just too frustrating to be unable to edit text without the full range of voice commands. (Dragon also does not learn if the "correct" commands are unavailable, so the same dictation mistakes occur ad infinitum.)
I hope you find out what the problem is. Nuance support is actually very responsive and supportive. Since you have just installed DPI 15, I am sure you are still within the support period they offer for installation problems. Maybe they can help :-)
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