If you just rename the directories, you can run into problems having the path saved somewhere in your workspace. This is now the case for your tc-server runtime. You can change that via "Preferences -> Server -> Runtime Environments", but I would strongly recommend to re-install a fresh STS to a right location to avoid other mismatches with your renamed folders.
Yeap. I'm unable to save the Runtime Environments after changing it to point to the correct path. Anyway, I had no idea how to uninstall and re-install as a fresh STS. Noticed that STS menu is not available in the Start > All Programs menu. It isn't inside the add or remove programs which accessed from the Control panel either..Kindly advise how should I perform a fresh copy of installation.