The SPFILENOTIFY_TARGETEXISTS notification is sent to the callback routine if the file to be copied was queued with the SP_COPY_NOOVERWRITE flag and that file already exists in the target directory. It can be sent to the callback routine alone or combined, by using the OR operator, with the SPFILENOTIFY_LANGMISMATCH and/or SPFILENOTIFY_TARGETNEWER notifications.
SPFILENOTIFY_TARGETEXISTS
    Param1 = (UINT) FilePathInfo;
    Param2 = (UINT) 0;
 The callback routine should return one of the following values.
| Value | Meaning | 
|---|---|
| TRUE | Overwrite the file in the target directory. | 
| FALSE | Skip the current copy operation. | 
  Windows NT:  Use version 4.0 and later.
  Windows:  Use Windows 95 and later.
  Windows CE:  Unsupported.
  Header: Declared in setupapi.h.
Overview, Notifications, FILEPATHS, SetupCommitFileQueue, SetupDefaultQueueCallback, SetupInstallFile, SetupInstallFileEx, SetupInstallFromInfSection