Download/Retrieve Email from Gmail account in Delphi

In previous section, I introduced how to retrieve email over SSL connection. In this section, I will introduce how to download email from your Gmail account in Delphi.

Introduction

Gmail POP3 server address is pop.gmail.com. It requires SSL connection on 995 port, and you should use your Gmail email address as the user name for user authentication.

Gmail IMAP4 server address is imap.gmail.com. It requires SSL connection on 993 port, and you should use your Gmail email address as the user name for user authentication. For example: your email is gmailid@gmail.com, and then the user name should be gmailid@gmail.com.

To retrieve email from Gmail account, you need to enable POP3 or IMAP4 access in your gmail account settings.

Because Gmail POP3 server doesn’t work like normal POP3 server, it hides old emails automatically even the email was not deleted, so we suggest that you use IMAP4 protocol.

Server Port SSL Protocol
pop.gmail.com 995 SSL required Pop3
imap.gmail.com 993 SSL required Imap4 (recommended)

Important

If you got authentication error, you need to enable Allowing less secure apps or Sign in using App Passwords.

Another way is Gmail OAUH, please see Gmail IMAP OAUTH section.

Note

Remarks: All of examples in this section are based on first section: A simple Delphi project. To compile and run the following example codes successfully, please click here to learn how to create the test project and add reference to your project.

[Delphi Example - Retrieve email from Gmail account]

The following example codes demonstrate how to download email from Gmail account using IMAP4 protocol.

Because Gmail POP3 server doesn’t work like normal POP3 server, it hides old emails automatically even the email was not deleted, so we suggest that you use IMAP4 protocol.

Note

To get the full sample projects, please refer to Samples section.

unit Unit1;

interface

uses
    Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
    Dialogs, StdCtrls, EAGetMailObjLib_TLB;

type
    TForm1 = class(TForm)
        Button1: TButton;
        procedure Button1Click(Sender: TObject);
    private
        { Private declarations }
    public
        { Public declarations }
    end;

const
    MailServerPop3 = 0;
    MailServerImap4 = 1;
    MailServerEWS = 2;
    MailServerDAV = 3;

var
    Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var
    oServer: TMailServer;
    oClient: TMailClient;
    oTools: TTools;
    oMail: IMail;
    infos: IMailInfoCollection;
    oInfo: IMailInfo;
    localInbox, fileName: WideString;
    i: Integer;
begin

    try
        // set current thread code page to system default code page.
        SetThreadLocale(GetSystemDefaultLCID());
        oTools := TTools.Create(Application);

        // Create a folder named "inbox" under
        // current directory to store the email files
        localInbox := GetCurrentDir() + '\inbox';
        oTools.CreateFolder(localInbox);

        oServer := TMailServer.Create(Application);
        // Gmail IMAP server address
        oServer.Server := 'imap.gmail.com';
        oServer.User := 'gmailid@gmail.com';
        oServer.Password := 'testpassword';
        oServer.Protocol := MailServerImap4;

        // Enable SSL connection
        oServer.SSLConnection := true;

        // Set 993 IMAP SSL Port
        oServer.Port := 993;

        oClient := TMailClient.Create(Application);
        oClient.LicenseCode := 'TryIt';

        oClient.Connect1(oServer.DefaultInterface);
        ShowMessage('Connected!');

        infos := oClient.GetMailInfoList();
        ShowMessage(Format('Total %d email(s)', [infos.Count]));

        for i := 0 to infos.Count - 1 do
        begin
            oInfo := infos.Item[i];

            ShowMessage(Format('Index: %d; Size: %d; UIDL: ' + oInfo.UIDL,
            [oInfo.Index, oInfo.Size]));

            // Generate a random file name by current local datetime,
            // You can use your method to generate the filename if you do not like it
            fileName := localInbox + '\' + oTools.GenFileName(i) + '.eml';

            // Receive email from IMAP server
            oMail := oClient.GetMail(oInfo);

            ShowMessage('From: ' + oMail.From.Address + #13#10 +
                'Subject: ' + oMail.Subject);

            // Save email to local disk
            oMail.SaveAs(fileName, true);

            // Mark email as deleted from IMAP server
            oClient.Delete(oInfo);
        end;

        // Quit and expunge emails marked as deleted from IMAP server
        oClient.Quit;

    except
        on ep:Exception do
        ShowMessage('Error: ' + ep.Message);
    end;

end;

end.

Gmail IMAP OAUTH

By default, you need to enable “Allowing less secure apps” in Gmail/G Suite, then you can retrieve email with user/password IMAP4 authentication.

However Google will disable traditional user authentication in the future, switching to Google OAuth is strongly recommended now.

Or you can generate App Passwords and use this app password instead of your user password.

[Delphi Example - Retrieve unread/new email from Gmail account]

Because IMAP/EWS/WebDAV support read mail flag, with this feature, we can also retrieve unread/new email only from Gmail like this

unit Unit1;

interface

uses
    Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
    Dialogs, StdCtrls, EAGetMailObjLib_TLB;

type
    TForm1 = class(TForm)
        Button1: TButton;
        procedure Button1Click(Sender: TObject);
    private
        { Private declarations }
    public
        { Public declarations }
    end;

const
    MailServerPop3 = 0;
    MailServerImap4 = 1;
    MailServerEWS = 2;
    MailServerDAV = 3;

    // GetMailInfosParam Flags
    GetMailInfos_All = 1;
    GetMailInfos_NewOnly = 2;
    GetMailInfos_ReadOnly = 4;
    GetMailInfos_SeqRange = 8;
    GetMailInfos_UIDRange = 16;
    GetMailInfos_PR_ENTRYID = 32;
    GetMailInfos_DateRange = 64;
    GetMailInfos_OrderByDateTime = 128;

var
    Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var
    oServer: TMailServer;
    oClient: TMailClient;
    oTools: TTools;
    oMail: IMail;
    infos: IMailInfoCollection;
    oInfo: IMailInfo;
    localInbox, fileName: WideString;
    i: Integer;
begin

    try
        // set current thread code page to system default code page.
        SetThreadLocale(GetSystemDefaultLCID());
        oTools := TTools.Create(Application);

        // Create a folder named "inbox" under
        // current directory to store the email files
        localInbox := GetCurrentDir() + '\inbox';
        oTools.CreateFolder(localInbox);

        oServer := TMailServer.Create(Application);
        // Gmail IMAP server address
        oServer.Server := 'imap.gmail.com';
        oServer.User := 'gmailid@gmail.com';
        oServer.Password := 'testpassword';
        oServer.Protocol := MailServerImap4;

        // Enable SSL connection
        oServer.SSLConnection := true;

        // Set 993 IMAP SSL Port
        oServer.Port := 993;

        oClient := TMailClient.Create(Application);
        oClient.LicenseCode := 'TryIt';

        oClient.Connect1(oServer.DefaultInterface);
        ShowMessage('Connected!');

        // retrieve unread/new email only
        oClient.GetMailInfosParam.Reset();
        oClient.GetMailInfosParam.GetMailInfosOptions := GetMailInfos_NewOnly;

        infos := oClient.GetMailInfoList();
        ShowMessage(Format('Total %d unread email(s)', [infos.Count]));

        for i := 0 to infos.Count - 1 do
            begin
                oInfo := infos.Item[i];

                ShowMessage(Format('Index: %d; Size: %d; UIDL: ' + oInfo.UIDL,
                [oInfo.Index, oInfo.Size]));

                // Generate a random file name by current local datetime,
                // You can use your method to generate the filename if you do not like it
                fileName := localInbox + '\' + oTools.GenFileName(i) + '.eml';

                // Receive email from IMAP server
                oMail := oClient.GetMail(oInfo);

                ShowMessage('From: ' + oMail.From.Address + #13#10 +
                    'Subject: ' + oMail.Subject);

                // Save email to local disk
                oMail.SaveAs(fileName, true);

                // mark unread email as read, next time this email won't be retrieved again
                if not oInfo.Read then
                    oClient.MarkAsRead(oInfo, true);

                // if you don't want to leave a copy on server, please use
                //  oClient.Delete(oInfo);
                // instead of MarkAsRead
            end;

        // Quit and expunge emails marked as deleted from IMAP server
        oClient.Quit;

    except
        on ep:Exception do
            ShowMessage('Error: ' + ep.Message);
    end;

end;

end.

TLS 1.2

TLS is the successor of SSL, more and more Email servers require TLS 1.2 encryption now.

If your operating system is Windows XP/Vista/Windows 7/Windows 2003/2008/2008 R2/2012/2012 R2, and you got connection error with SSL/TLS connection, you need to enable TLS 1.2 protocol in your operating system like this:

Enable TLS 1.2 on Windows XP/Vista/7/10/Windows 2008/2008 R2/2012

Next Section

At next section I will introduce how to download emails from Yahoo account.

Appendix

Comments

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