Error For users in SQL SERVER , the User neither deleting nor modifying

ERROR:

An exception occurred while executing a Transact-SQL statement or batch (Microsoft SQL Server, Error: 15023)

The complate Error is
Microsoft SQL Server Management Studio ------------------------------  Create failed for User 'apuser'.  (Microsoft.SqlServer.Smo)  For help, click: https://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&ProdVer=15.0.18206.0+((SSMS_Rel).191029-2112)&EvtSrc=Microsoft.SqlServer.Management.Smo.ExceptionTemplates.FailedOperationExceptionText&EvtID=Create+User&LinkId=20476  ------------------------------ ADDITIONAL INFORMATION:  An exception occurred while executing a Transact-SQL statement or batch. (Microsoft.SqlServer.ConnectionInfo)  ------------------------------  User, group, or role 'apuser' already exists in the current database. (Microsoft SQL Server, Error: 15023)

Many times the situation occurred as the SQL SERVER USER neither can be created nor modified throwing the above error. Even the user deleted and created again giving the same error again and again . To rectify this..

sp_change_users_login 'AUTO_FIX', 'someuser'   -- here the user is 'apuser' so the command is

sp_change_users_login 'AUTO_FIX', 'apuser'

The output of the command should be

The row for user ‘apuser’ will be fixed by updating its login link to a login already in existence.

The number of orphaned users fixed by updating users was 1.

The number of orphaned users fixed by adding new logins and then updating users was 0.

The output may different depending on issues, if the issues not there then it will be shown as 0 each.. the command will solve most of the issues , After executing the above test the user creation or modification once again.. if problem still persisting

First of all run following T-SQL Query in Query Analyzer. This will return all the existing users in database in result pan.
USE YourDB
GOEXEC sp_change_users_login 'Report'GO

Run following T-SQL Query in Query Analyzer to associate login with the username. ‘Auto_Fix’ attribute will create the user in SQL Server instance if it does not exist. In following example ‘ColdFusion’ is UserName, ‘cf’ is Password. Auto-Fix links a user entry in the sysusers table in the current database to a login of the same name in sysxlogins.

USE YourDB
GOEXEC sp_change_users_login 'Auto_Fix', 'apuser', NULL, 'cf'GO

After proceeding the above steps check once again
If the problem persisting delete the user and create again by using the following command

USE YourDB
GOEXEC sp_dropuser 'apuser'GO

Delete the user by selecting the assigned database only

Consuming Webserive in DOTNET C#.net C sharp .net

Here I am consuming test webservice of Meeseva

Lets Create a sample Application

I am taking a DropDown to check whether the user having Income Certificate or not. If so the certificate number is supplied to our application and after pressing getData button the details of the certificate are populated and shown in our application.

To do this lets create our design page i.e., income.aspx page..

Create a panel with the controls:

 <asp:Panel ID="income_panel" runat="server">
                <table>
                    <tr>
                        <td colspan="2" align="center" style="font-size: 20px; font-weight: bold; color: darkblue">Consuming Web Service
                            <br />
                            <br />
                        </td>
                    </tr>
                    <tr>
                        <td align="right" style="width: 50%">
                            <asp:Label ID="Label99" runat="server" Font-Bold="true" Text="Do you belongs to Fee-Exemption  category ? (Y/N):"></asp:Label>
                        </td>
                        <td align="left" class="auto-style1">
                            <asp:DropDownList ID="ddl_income" runat="server" Width="93px" AutoPostBack="True" Height="30px" OnSelectedIndexChanged="ddl_income_SelectedIndexChanged">
                                <asp:ListItem Selected="True" Value="1">--Select--</asp:ListItem>
                                <asp:ListItem Value="N">NO</asp:ListItem>
                                <asp:ListItem Value="Y">YES</asp:ListItem>
                            </asp:DropDownList>
                        </td>
                    </tr>
                    <tr>
                        <td colspan="2" align="center" style="width: 50%">
                            <asp:Label ID="lbl_inc_msg" runat="server" Font-Bold="true" ForeColor="Green" Font-Size="15px"></asp:Label>
                        </td>
                    </tr>
                    <tr>
                        <td align="right">
                            <asp:Label ID="lbl_inc_cer" runat="server" Font-Bold="true" Text="Enter Income Certificate No :"></asp:Label>

                        </td>
                        <td align="left" class="auto-style1">
                            <br />
                            <asp:TextBox ID="txt_inc" runat="server" ValidationGroup="income" MaxLength="14"></asp:TextBox>
                            <asp:Button ID="btn_income" runat="server" Text="GetData" OnClick="btn_income_Click" />
                            <asp:RequiredFieldValidator ID="rqfv_income_no" runat="server" ErrorMessage="*Required" ControlToValidate="txt_inc" ValidationGroup="income" ForeColor="Red"></asp:RequiredFieldValidator>
                            <asp:RegularExpressionValidator ID="rgfv_income_no" runat="server" ErrorMessage="Invalid Income Certificate Number" ControlToValidate="txt_inc" ValidationGroup="income" ForeColor="Red" ValidationExpression="IC[0-9]{12,12}"></asp:RegularExpressionValidator>
                        </td>
                    </tr>
                    <tr>
                        <td colspan="2">
                            <div id="div_inc_online" runat="server">
                                <table width="100%" class='box'>
                                    <tr style="background-color: aquamarine">
                                        <td colspan="2" align="center" style="font-size: 20px; font-weight: bold; color: green">Online Income Certificate Details</td>
                                    </tr>
                                    <tr>
                                        <td align="right">
                                            <asp:Label ID="Label10" runat="server" Font-Bold="true" Text="Certificate Number :"></asp:Label>
                                        </td>
                                        <td align="left">
                                            <asp:Label ID="lbl_inc_cer_no" runat="server"></asp:Label>
                                        </td>
                                    </tr>
                                    <tr>
                                        <td align="right">
                                            <asp:Label ID="Label14" runat="server" Font-Bold="true" Text="Name:"></asp:Label>
                                        </td>
                                        <td align="left">
                                            <asp:Label ID="lbl_inc_name" runat="server"></asp:Label>
                                        </td>
                                    </tr>
                                    <tr>
                                        <td align="right">
                                            <asp:Label ID="Label18" runat="server" Font-Bold="true" Text="Father Name:"></asp:Label>
                                        </td>
                                        <td align="left">
                                            <asp:Label ID="lbl_inc_fname" runat="server"></asp:Label>
                                        </td>
                                    </tr>
                                    <tr>
                                        <td align="right">
                                            <asp:Label ID="Label20" runat="server" Font-Bold="true" Text="Date of Birth:"></asp:Label>
                                        </td>
                                        <td align="left">
                                            <asp:Label ID="lbl_inc_dob" runat="server"></asp:Label>
                                        </td>
                                    </tr>
                                    <tr>
                                        <td align="right">
                                            <asp:Label ID="Label22" runat="server" Font-Bold="true" Text="Total Income:"></asp:Label>
                                        </td>
                                        <td align="left">
                                            <asp:Label ID="lbl_inc_inc" runat="server"></asp:Label>
                                        </td>
                                    </tr>
                                </table>
                            </div>
                        </td>
                    </tr>
                   
                </table>
          <asp:HiddenField ID="hid_mobile" runat="server"></asp:HiddenField>
            </asp:Panel>

The Image of the page looks like








Now Lets create our CS page with the code behind for each control:

The CS Code is

 protected void Page_Load(object sender, EventArgs e)
    {
        lbl_inc_cer.Visible = false;
        txt_inc.Visible = false;
        income_panel.Visible = false;

        lbl_inc_cer_no.Visible = false;

        lbl_inc_msg.Text = "";

        btn_income.Visible = false;
    }

    protected void ddl_income_SelectedIndexChanged(object sender, EventArgs e)
    {
        if (ddl_income.SelectedValue == "Y")
        {
            lbl_inc_cer.Visible = true;
            txt_inc.Visible = true;
            income_panel.Visible = true;
         
            lbl_inc_cer_no.Visible = true;

            lbl_inc_msg.Text = "";
        
            btn_income.Visible = true;
        }
        else
        {
            lbl_inc_cer.Visible = false;
            txt_inc.Visible = false;
            income_panel.Visible = false;
           
            lbl_inc_cer_no.Visible = false;

            lbl_inc_msg.Text = "";
         
            btn_income.Visible = false;
        }
    }

    protected void btn_income_Click(object sender, EventArgs e)
    {
        this.Validate();
        if (!this.IsValid) return;
        Get_service_data();
        div_inc_online.Visible = true;
        //string mobile = Session["mobileno"].ToString();
        string mobile = hid_mobile.Value.ToString();
     
    }

    public void Get_service_data()
    {
        XmlDocument xmldoc = new XmlDocument();
        string uname, pwd;
        uname = "APCET";
        pwd = "************"; // Provide the Password Here

  IncomeService.MeeSevaTransactions CI = new IncomeService.MeeSevaTransactions();


        if (txt_inc.Text == "")
        {
            lbl_inc_msg.Text = "Certificate Number not given";
            return;
        }
        else if (txt_inc.Text != "")
        {
            string inc_cer_no = txt_inc.Text;
            string response;
            try
            {
                response = CI.GetDetailsByAppNo(inc_cer_no, uname, pwd);
                xmldoc.LoadXml(response);
                //Response.Write("meeseva income Response:" + response.ToString().Trim());

            }
            catch (Exception ex)
            {
                // Response.Write("Meeseva Service Error" + ex.Message.ToString());
                ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "alertMessage", "alert('Not Fetching the Data from Service.Please try again.')", true);
            
                div_inc_online.Visible = false;


            }

            if (xmldoc.SelectSingleNode("//Application_Number") != null)
            {
                if (xmldoc.SelectSingleNode("//Applicant_Name") != null)
                    lbl_inc_name.Text = xmldoc.SelectSingleNode("//Applicant_Name").InnerText;
                if (xmldoc.SelectSingleNode("//FatHus_Name") != null)
                    lbl_inc_fname.Text = xmldoc.SelectSingleNode("//FatHus_Name").InnerText;
                if (xmldoc.SelectSingleNode("//Date_Of_Birth") != null)
                    lbl_inc_dob.Text = xmldoc.SelectSingleNode("//Date_Of_Birth").InnerText;
                if (xmldoc.SelectSingleNode("//Application_Number") != null)
                    lbl_inc_cer_no.Text = xmldoc.SelectSingleNode("//Application_Number").InnerText;
                if (xmldoc.SelectSingleNode("//Total_Income") != null)
                    lbl_inc_inc.Text = xmldoc.SelectSingleNode("//Total_Income").InnerText;

                //Send OTP
                string mobile = hid_mobile.Value.ToString();
                    
            }
            else
            {
                ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "alertMessage", "alert('No Data Available .')", true);

            }
        }


    }

So Now the IncomeService is to be included in our Project To do this follow the steps

Adding a Web Service Reference in the ASP.Net Web Application

The most important task when consuming a Web Service in an ASP.Net Web Application is adding the Web Service reference into the ASP.Net web application. So how to add it? Let us see the procedure.

Right-click on the ASP.Net Web Application and click on "Add Service Reference" as in the following:

 

 Now Give the URL provided for you in the following dialog BOX

 After Providing the URL click Go, the service is populated in the below Dialog where the services are shown.. And provide a Namespace , Here I have given as "IncomeService"

Click on Advanced Button, 

Click On Add Web Reference button in the advanced dialog box ,

Click the AddReference Button, You will get a new web reference in Solution Explorer

As shown in above Picture, Now Run the Program note that the Same Webservice name used in our CS page Which was highlighted in CS Code i.e., IncomeService