getting error when inserting data into data base

Question

when click on submit button getting error as

 

" Implicit conversion from data type varchar to varbinary is not allowed. Use the CONVERT function to run this query."

 

my c# code :-

protected void Button1_Click(object sender, EventArgs e)
{
if (RadioButton1.Checked)
{
Gender = "Male";
}
else if (RadioButton2.Checked)
{
Gender = "Female";
}
else if (RadioButton3.Checked)
{
Gender = "Other";
}
if (RadioButton4.Checked)
{
Relationship = "Father";
}
else if (RadioButton5.Checked)
{
Relationship = "Mother";
}
a = Class1.GetRandomPassword(5).ToString();
FileUpload1.SaveAs(Request.PhysicalApplicationPath + "./images/registration/" + a + FileUpload1.FileName.ToString());
a1 = "images/registration" + a + FileUpload1.FileName.ToString();
b = Class1.GetRandomPassword(5).ToString();
FileUpload2.SaveAs(Request.PhysicalApplicationPath + "./images/registration/" + b + FileUpload2.FileName.ToString());
b2 = "images/registration" + b + FileUpload2.FileName.ToString();
c = Class1.GetRandomPassword(5).ToString();
FileUpload3.SaveAs(Request.PhysicalApplicationPath + "./images/registration/" + c + FileUpload3.FileName.ToString());
c3 = "images/registration" + c + FileUpload3.FileName.ToString();
d = Class1.GetRandomPassword(5).ToString();
FileUpload4.SaveAs(Request.PhysicalApplicationPath + "./images/registration/" + d + FileUpload4.FileName.ToString());
d4 = "images/registration" + d + FileUpload4.FileName.ToString();
g = Class1.GetRandomPassword(5).ToString();
FileUpload5.SaveAs(Request.PhysicalApplicationPath + "./images/registration/" + g + FileUpload5.FileName.ToString());
g5 = "images/registration" + g + FileUpload5.FileName.ToString();
f = Class1.GetRandomPassword(5).ToString();
FileUpload6.SaveAs(Request.PhysicalApplicationPath + "./images/registration/" + f + FileUpload6.FileName.ToString());
f6 = "images/registration" + f + FileUpload6.FileName.ToString();
con.Open();
SqlCommand cmd = con.CreateCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = "insert into registration values('" + TextBox1.Text + "','" + TextBox2.Text + "','" + Gender + "','" + dob.Text + "','" + TextBox3.Text + "','" + TextBox4.Text + "','" + TextBox5.Text + "','" + TextBox6.Text + "','" + TextBox7.Text + "','" + TextBox8.Text + "','" + TextBox9.Text + "','" + TextBox10.Text + "','" + TextBox11.Text + "','" + TextBox12.Text + "','" + TextBox13.Text + "','" + TextBox14.Text + "','" + TextBox15.Text + "','" + TextBox16.Text + "','" + TextBox17.Text + "','" + TextBox18.Text + "','" + TextBox19.Text + "','" + TextBox20.Text + "','" + TextBox21.Text + "','" + TextBox22.Text + "','" + Relationship + "','" + TextBox23.Text + "','" + TextBox24.Text + "','" + TextBox25.Text + "','" + TextBox26.Text + "','" + a1.ToString() + "','" + b2.ToString() + "','" + c3.ToString() + "','" + d4.ToString() + "','" + g5.ToString() + "','" + f6.ToString() + "')";
cmd.ExecuteNonQuery();
con.Close();
}