Velocity Reviews - Runtime Error c++

Hi there .this code has this error runtime :
Windows has triggered a breakpoint in a.exe.
This may be due to a corruption of the heap, which indicates a bug in a.exe or any of the DLLs it has loaded.
This may also be due to the user pressing F12 while a.exe has focus.

[code]
#include<stdio.h>
#include<stdlib.h>
#include<windows.h>
#include<winbase.h>
#include<process.h>
#include<winreg.h>
#include<tlhelp32.h>
#include<iostream>
#include<ctime>
usingnamespace std;
bool checkDir(LPSTR s){
FILE *fp;
fp=fopen(s,"r");
/* If we can't open it as file in read mode then it can be directory */
if(fp){
fclose(fp);
returnfalse;
}
returntrue;
} void exploreDirectory(char *s)
{ int ln=strlen(s);
strcat(s,"\\*");
WIN32_FIND_DATA FindFileData;
HANDLE hFind;
hFind = FindFirstFile((LPWSTR)s, &FindFileData);
LPSTR str=(char *)malloc(260);
strcpy(str,s);
int len;
do{
str[ln+1]=0;
strcat(str,(constchar *)FindFileData.cFileName);
if(!strcmp((constchar *)FindFileData.cFileName,".")||!strcmp((constchar *)FindFileData.cFileName,"")||!strcmp((constchar *)FindFileData.cFileName,".."))continue;
if(checkDir(str)){
// we have got directory
exploreDirectory(str);
}else{
// we got a file..... do what you want to do
cout<<str<<endl; cout<<FindFileData.cFileName<<endl;
}
}while(FindNextFile(hFind, &FindFileData));
FindClose(hFind);
}
int main()
{
char path[260]={"c:"};
exploreDirectory(path);
}
[\code]

please help me:yell: