Cần giúp về file C++ có đường dẫn tới ổ E?

Sao em ghi vào ổ E ko đc vậy?

Em chạy tới đoạn này thì bị báo là Ko mo duoc tap tin!

int main()
{
    sv a;
    nhapsv(a);
    insv(a);
    ghifilevb("E:/sinhvien3.txt",a);

    return 0;
}

Đây là nội dung hàm: ghifilevb

void ghifilevb (char fname[], sv s)
{
    FILE *fp;

    fp = fopen(fname,"wt");

    if (!fp)
    {
        cout <<"Ko mo duoc tap tin!
";
        return ;
    }
    /*while (!feof(fr)){
        fgets(s, fr);
        fputs(s,fw);
    }*/

    //cout<<endl<<"MSSV: "<<s.mssv<<endl<<endl;
    while (!feof(fp))
    {
        fgets(s.mssv,9,fp);
    }

    fprintf(fp,"
");
    //cout<<"ho & ten SV: "<<s.hoten<<endl<<endl;
    while (!feof(fp))
    {
        fgets(s.hoten,100,fp);
    }

    fprintf(fp,"
");
    //cout<<"so mon hoc: "<<s.somon<<endl<<endl;
    fprintf(fp,"%d
", s.somon);

    //cout<<"Tong TC: "<<tongtc(s)<<endl<<endl;
    fprintf(fp,"%d
", tongtc(s));
    //cout<<"Tong TC tich luy: "<<tongtctl(s)<<endl<<endl;
    fprintf(fp,"%d
", tongtctl(s));
    //cout<<"diem TB: "<<dtb(s)<<endl<<endl;
    fprintf(fp,"%d
", dtb(s));
    //cout <<"diem TBTL: "<<dtbtl(s)<<endl<<endl;
    fprintf(fp,"%d
", dtbtl(s));

    // cout<<s.kq[i].mamh<<"	"<<s.kq[i].tenmh<<"			"<<s.kq[i].sotc<<"	"<<s.kq[i].diem;
    for(int i=0; i<s.somon; i++)
    {
        fprintf(fp,"===========================
");
        fprintf(fp,"%d
", s.kq[i].mamh);
        while (!feof(fp))
        {
            fgets(s.kq[i].tenmh,50,fp);
        }

        fprintf(fp,"
");
        fprintf(fp,"%d
", s.kq[i].sotc);
        fprintf(fp,"%d
", s.kq[i].diem);
        fprintf(fp,"===========================
");
    }
    fclose(fp);
}

Đây là toàn bộ code:

#include <iostream>
#include <ctype.h>
#include <string.h>
#include "stdio.h"

using namespace std;

typedef struct MH
{
    int mamh;// ma mon hoc
    char tenmh[50];// ten mon hoc
    int sotc;
    int diem;
};

typedef struct sv
{
    char mssv[9];
    char hoten[100];
    int somon;
    MH kq[100];
    int tctl,tongtc;
    double dtbc,dtbtl;
};

//cac ham con
void nhapmh(MH &m);
void nhapsv(sv &s);
void insv(sv s);
int tongtc(sv s);
int tongtctl(sv s);
double dtb(sv s);
double dtbtl(sv s);
//ghi file
void ghifilevb (char fname[], sv s);

int main()
{
    sv a;
    nhapsv(a);
    insv(a);
    ghifilevb("E:/sinhvien3.txt",a);

    return 0;
}

//cac ham con
void nhapsv(sv &s)
{
    cout<<"nhap MSSV: ";
    cin.getline(s.mssv,9);
    cout<<"nhap ho ten: ";
    cin.getline(s.hoten,100);
    cout<<"so mon hoc: ";
    cin>>s.somon;
    cout<<"nhap thong tin cac mon: 
";
    for(int i=0; i<s.somon; i++)
    {
        cout<<"nhap ma mon thu "<<i<<" : ";
        cin>>s.kq[i].mamh;

        cout<<"nhap ten mon thu "<<i<<" : ";
        cin.ignore();
        cin.getline(s.kq[i].tenmh,50);

        cout<<"nhap diem mon thu " <<i<<": ";
        cin>>s.kq[i].diem;

        cout<<"nhap tchi mon thu "<<i<<": ";
        cin>>s.kq[i].sotc;
    }
}
void insv(sv s)
{
    cout<<endl<<endl<<endl;

    cout<<"----------THONG TIN SINH VIEN-----------";
    cout<<endl<<endl<<endl;

    cout<<endl<<"MSSV: "<<s.mssv<<endl<<endl;
    cout<<"ho & ten SV: "<<s.hoten<<endl<<endl;
    cout<<"so mon hoc: "<<s.somon<<endl<<endl;

    cout<<"Sinh vien "<<"""<<s.hoten<<"""<<" co cac thong so sau: "<<"

";
    cout<<"Tong TC: "<<tongtc(s)<<endl<<endl;
    cout<<"Tong TC tich luy: "<<tongtctl(s)<<endl<<endl;
    cout<<"diem TB: "<<dtb(s)<<endl<<endl;
    cout <<"diem TBTL: "<<dtbtl(s)<<endl<<endl;
    cout<<"====================================================="<<endl;
    cout<<"-------------------DIEM CHI TIET---------------------"<<endl;
    cout<<"====================================================="<<endl;
    cout<<"Ma MH"<<"	"<<"Ten MH"<<"			"<<"So TC"<<"	"<<"Diem"<<endl;
    cout<<"====================================================="<<endl;
    for(int i=0; i<s.somon; i++)
    {
        cout<<s.kq[i].mamh<<"	"<<s.kq[i].tenmh<<"			"<<s.kq[i].sotc<<"	"<<s.kq[i].diem;
        cout<<endl<<endl;
    }
}
int tongtc(sv s)
{
    int s1=0;
    for(int i=0; i<s.somon; i++)
    {
        s1 += s.kq[i].sotc;
    }

    return s1;
}

int tongtctl(sv s)
{
    int s1=0;
    for(int i=0; i<s.somon; i++)
    {
        if(s.kq[i].diem>=5)
            s1 += s.kq[i].sotc;
    }

    return s1;
}
double dtb(sv s)
{
    int s1=0;
    for(int i=0; i<s.somon; i++)
    {
        s1 += s.kq[i].diem*s.kq[i].sotc;
    }

    double s2 = (double)s1/(tongtc(s));
    return s2;
}
double dtbtl(sv s)
{
    int s1=0;
    for(int i=0; i<s.somon; i++)
    {
        if(s.kq[i].diem>=5)
            s1 += s.kq[i].diem*s.kq[i].sotc;
    }

    double s2 = (double)s1/(tongtctl(s));
    return s2;
}

//7. in danh sach nhung mon hoc con no
void danhsachno(sv s)
{
    cout<<"nhung mon con no la: "<<endl;
    for(int i=0; i<s.somon; i++)
    {
        if(s.kq[i].diem<5)
            cout<<"mon thu "<<i;
        cout<<endl;
    }
}
void ghifilevb (char fname[], sv s)
{
    FILE *fp;

    fp = fopen(fname,"wt");

    if (!fp)
    {
        cout <<"Ko mo duoc tap tin!
";
        return ;
    }
    /*while (!feof(fr)){
        fgets(s, fr);
        fputs(s,fw);
    }*/

    //cout<<endl<<"MSSV: "<<s.mssv<<endl<<endl;
    while (!feof(fp))
    {
        fgets(s.mssv,9,fp);
    }

    fprintf(fp,"
");
    //cout<<"ho & ten SV: "<<s.hoten<<endl<<endl;
    while (!feof(fp))
    {
        fgets(s.hoten,100,fp);
    }

    fprintf(fp,"
");
    //cout<<"so mon hoc: "<<s.somon<<endl<<endl;
    fprintf(fp,"%d
", s.somon);

    //cout<<"Tong TC: "<<tongtc(s)<<endl<<endl;
    fprintf(fp,"%d
", tongtc(s));
    //cout<<"Tong TC tich luy: "<<tongtctl(s)<<endl<<endl;
    fprintf(fp,"%d
", tongtctl(s));
    //cout<<"diem TB: "<<dtb(s)<<endl<<endl;
    fprintf(fp,"%d
", dtb(s));
    //cout <<"diem TBTL: "<<dtbtl(s)<<endl<<endl;
    fprintf(fp,"%d
", dtbtl(s));

    // cout<<s.kq[i].mamh<<"	"<<s.kq[i].tenmh<<"			"<<s.kq[i].sotc<<"	"<<s.kq[i].diem;
    for(int i=0; i<s.somon; i++)
    {
        fprintf(fp,"===========================
");
        fprintf(fp,"%d
", s.kq[i].mamh);
        while (!feof(fp))
        {
            fgets(s.kq[i].tenmh,50,fp);
        }

        fprintf(fp,"
");
        fprintf(fp,"%d
", s.kq[i].sotc);
        fprintf(fp,"%d
", s.kq[i].diem);
        fprintf(fp,"===========================
");
    }
    fclose(fp);
}