How to add your Gmail account to Thunderbird

Step-by-Step Guide to Adding Gmail to Thunderbird :
1. Enable IMAP in Gmail
Open Gmail: First, log into your Gmail account using your usual credentials.
Go to Settings: Click the gear icon at the top right of your Gmail inbox, then select See all settings from the dropdown menu.
Enable IMAP: In the Forwarding and POP/IMAP tab, look for the IMAP Access section and select Enable IMAP. This will allow Thunderbird to access your Gmail account and sync your emails. After enabling, click Save Changes to confirm.
2. Open Thunderbird
Launch Thunderbird on your computer. If you don't have Thunderbird installed yet, download and install it from the Thunderbird website.
3. Add New Mail Account
Inside Thunderbird, click on the File menu located at the top left of the window, then select New and choose Existing Mail Account… from the dropdown list. This will bring up the Mail Account Setup dialog box.
4. Enter Your Gmail Details
In the setup dialog, enter the following details:
Your Name: This is the name that will be displayed when you send emails.
Email Address: Enter your full Gmail address (e.g., yourname@gmail.com).
Password: Enter the password for your Gmail account. Thunderbird will try to automatically configure the necessary settings for Gmail.
Thunderbird will detect Gmail's IMAP settings automatically and move on to the next step.
5. Sign in with OAuth
Due to security measures, OAuth is now required to access Gmail. Once Thunderbird has configured your account, you will be prompted to sign in to your Google account.
You’ll need to enter your Gmail credentials (email and password).
After entering your credentials, a Google page will appear asking for permission to let Thunderbird access your Gmail account. Click Allow to grant Thunderbird access securely via OAuth.
6. Sync Gmail Labels as Folders
Gmail Labels as Thunderbird Folders: Gmail uses labels to categorize emails, and Thunderbird syncs these labels as folders. So, when you apply a label to a message in Gmail, Thunderbird will create a folder with the same name to store that message.
Similarly, if you move a message to a folder in Thunderbird, Gmail will create a corresponding label for it. This syncing ensures that both Thunderbird and Gmail reflect your email organization system.
Important Tip: When you move or copy an email to a folder in Thunderbird, Gmail will store only one copy of that email but apply multiple labels if needed. This allows you to access it from various folders.
7. Manage Folder Subscriptions
Thunderbird gives you the ability to manage which folders you want to display and synchronize. To do this:
Right-click your Gmail account in the Thunderbird folder pane and select Subscribe.
In the Subscription Manager, uncheck folders you don’t want to display in Thunderbird.
For performance reasons, it is recommended that you unsubscribe from the "All Mail" folder since it contains all messages, including those in your inbox and archived emails. This can save storage space and improve synchronization speed.
8. Adjust Synchronization Settings
Sync Settings for Better Performance: Thunderbird lets you control how emails are downloaded and synchronized to improve performance and reduce local storage usage.
Go to Account Settings > Synchronization & Storage.
Here, you can choose to download only message headers for selected folders, which will reduce download times and storage usage. Emails will only be fully downloaded when you open them.
You can also enable or disable synchronization for specific folders based on your preferences.

Your Gmail Account is Now Set Up in Thunderbird!
Congrats! Your Gmail account is now successfully integrated with Thunderbird. All your emails, labels, and folders are synced seamlessly, and you can enjoy the benefits of using Gmail through the Thunderbird email client. You can manage your emails efficiently, just like you would on the Gmail web interface, but with the added convenience of offline access and advanced email organization features.

Additional Features and Tips
Gmail's Special Folders in Thunderbird: In addition to your custom labels, Thunderbird will display a set of default Gmail folders such as:
All Mail: This contains all your Gmail messages, including sent and archived emails.
Sent Mail: All your sent messages appear here.
Drafts: For any unsent emails you’ve saved as drafts.
Spam: This folder contains messages that Gmail has flagged as spam.
Trash: Deleted emails are stored here.
Adjust Thunderbird’s Filtering and View Options:
To ensure that Thunderbird’s message list matches Gmail’s filtering, you can adjust Thunderbird’s settings to work with Gmail’s Conversation View and Filtering options. This way, emails will be grouped by conversations, just like in Gmail.
Access Gmail via Thunderbird on Multiple Devices: You can set up Thunderbird on multiple devices and ensure that all your Gmail data, labels, and emails are synchronized across them for a consistent experience.
For More Details : https://getmehuman.com/thunderbird-email/
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