Turbo C dates back to 1989, 22 years ago. Odds are that it is no longer compatible with the current version of Windows.
I recommend that you upgrade to a more recent C compiler. If you really, really don't want to upgrade to a new compiler, do a complete system backup and then download the XP compatibility package for Win7. See if you can install TC and run it under that. If it messes up your system, restore that backup.
If you are programming in C,it's worth investing the time in learning to use an Integrated Development Environment such as Eclipse. It takes some time to learn, but does make the development cycle easier on the brain in the long run. http://www.eclipse.org/callisto/c-dev.php