The DdeUninitialize function frees all Dynamic Data Exchange Management Library (DDEML) resources associated with the calling application.
BOOL DdeUninitialize(
| DWORD idInst | // instance identifier | 
| ); | 
If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero.
DdeUninitialize terminates any conversations currently open for the application.