Turbo C is not compatible with windows vista and windows 7. Turbo C and Turbo C++ is only compatible with Windows XP and Less. Do the Following Steps, It will help you :
Install the software DOSBox ver 0.72 ( 1.2 MB ) (Freeware) from the link below (Direct Link)
Before going to the details u have to create a folder (any name will do). Here we name it as Turbo
Copy the TC into the Turbo folder
Run the DOSBox 0.72 from the icon located on the desktop or from the location of the installation folder
Then u are presented with two screens which look like the command prompt in Windows
Now u are presented with two screens. One with a Z prompt. U can ignore the other screen.
There type the following commands at the command prompt [Z]:
Mount [Type in any alphabet that u wish except z] [Type the source of the turbo C] press enter
Now , Type in the following commands after the Z prompt:
Z: mount d c:\Turbo\ [The folder TC is present inside the folder Turbo]
* Now u should get a message which says: Drive D is mounted as a local directory c:\Turbo\ ***
Now type d: to shift to d: prompt .
D: cd TC [The contents inside the folder Turbo gets mounted as a virtual drive (Here D drive)
D: cd Bin
D: TC or Tc.exe [This presents u the Turbo C++3.0 screen]
On the Turbo C++ goto Options>Directories>Change the source of TC to the source directory [D] ( i.e. virtual D: refers to original c:\Turbo\ . So make the path change to something like D:\TC\include and D:\TC\lib respectively )
In order to get the full screen use the key combination of Alt and Enter
When u exit from the DosBox [precisely when u unmount the virtual drive where Turbo C++ 3.0 has been mounted] all the files u have saved or made changes in Turbo C++ 3.0 will be copied into the source directory(The directory which contains TC folder)
It is a good idea to backup your files in the source directory prior to running DOSBox 0.72
For additional help go through the readme file located in the installation folder or look on the website of the DOSBox forum.
The above procedure has been successfully implemented on Windows Vista Ultimate 64 bit
IMP : Don't use shortcut keys to perform operations in TC because they might be a shortuct key for DOSBOX also . Eg : Ctrl+F9 will exit DOSBOX rather running the code .
This might help you to solve the problem.