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Web-based email providers, like Google's Gmail, let you check and send messages on any computer in the world via the web browser. You can sign in at home, work, school, or anywhere, without having to install or configure an email client, such as Outlook or Thunderbird.
The downside is that you must be online the whole time while reading and composing the emails. However, Google's new Offline Gmail feature lets you read or compose messages without being online. While you're in-flight, on the road, not around a network, or otherwise not connected, you can write up emails to be sent later or read your downloaded messages. I’ll discuss using and setting up this new feature, as well as Gmail access with client applications.
Offline email access
When you have an email client application configured with a provider, you only have to get online to synchronize your email. While offline, you can compose messages and hit Send, which moves them to the Outbox. Plus you can read messages from others, and open their attachments, that have been downloaded to your computer during the synchronization. When you get online again, any messages in the Outbox will be sent and any new messages on the server will be retrieved.
To help users have this offline capability with Gmail, Google Labs recently released Offline Gmail. It uses Google's Gears plug-in, which lets you download web applications and run them in the browser without having to be online. So when installed, Offline Gmail opens in your browser and shows the Gmail web-based interface, where you can read and compose messages, whether or not you are online.
Just like with other email clients, when you get back online it synchronizes your email. When using Offline Gmail, you almost don't notice you are offline, other than not being able to actually send the messages or retrieve new ones.
Being able to check and write-up messages while offline with Gmail isn't a new thing. From day one, Gmail has offered POP3/IMAP access to their servers. You can use an email client application to check and send messages via your Gmail account. However, this involves more installation and/or configuration time. If you already use a client application, though, adding your Gmail account provides a single, universal, email application or location. Otherwise, if Gmail is your primary email provider, using Offline Gmail is probably the way to go.
Setting up and using Offline Gmail
If you want to try out the new Office Gmail feature, log into your Gmail account, click the Settings link in the upper right corner, and then click the Labs tab. In the Offline section, select Enable, and then click Save Changes. Then after your browser reloads, you'll see a new "Offline 0.1" link next to your username, in the upper right-hand corner of the browser. To start the automated installation of the feature and Gears, click that link.
From now when you go to Gmail, when you are online, it will automatically synchronize by downloading new messages to your computer. Therefore, if you disconnect from the Internet, you'll still be able to read them. Additionally, you can double-click the Gmail icon on your desktop, start menu, or quick start menu when offline to bring up the local offline version of Gmail's interface. You can also use this shortcut when online, which will just bring up the regular interface.
There are only minimal differences in the offline and online interfaces; when offline, you can't change some settings. To check the status of Offline Gmail, hover over the new icon in the upper right corner of the web browser.
If you are using an unrealizable Internet connection, such as a distant Wi-Fi hotspot, you can put Offline Gmail into Flaky Connection Mode. This makes Gmail use the downloaded or cached data as if you were disconnected, but continues to automatically synchronizes your mail. This might prevent errors when you loose Internet connectivity during sending messages or changing settings. To toggle the Flaky Connection Mode on or off, simply hover over the icon in the upper right corner of the web browser and click the link.
Configuring and using a email client
If you rather use a email client application, you must first choose the access type, POP3 (called just POP in Gmail) or IMAP. Using IMAP is great if you check your email from multiple computers or devices, as the messages always remains on the server. The messages in the folders (Inbox, Drafts, Old, Sent, etc.) will appear the same among all the computers. POP3 access doesn’t provide this email storage feature. Once messages are checked with POP3 they are downloaded to the client and messages can't be retrieved later with other clients.
The catch about IMAP is that the amount of messages that can be saved on the server is limited to the shortage space you're allowed to use. For example, Gmail currently gives you over 7 gigabytes. This is probably more than enough if you're okay with permanently deleting some of your old messages, but if you want to keep an archive of all messages and their attachments indefinitely, you might run into problems down the road.
Once you choose the access type, you must enable it for your Gmail account. Log into your account, click the Settings link, and click the Forwarding and POP/IMAP tab. Then select the enable option for either POP or IMAP and hit Save Changes.
Now you can configure your email client application. The server address for incoming email is pop.gmail.com for POP3 access (on the SSL 995 port) and imap.gmail.com for IMAP access (on the SSL 993 port). The outgoing mail server (SMTP) is smtp.gmail.com for both access types (on the SSL 965 port) with authentication. For the server login credentials, use your Gmail email address for the username and its password for the server password.
For step-by-step instructions on configuring particular client applications, use Gmail's Configuration Instructions from the Forwarding and POP/IMAP section of your account settings.
Try other Gmail Lab projects
I’ve covered how offline email access can be convenient, the advantages/disadvantages of Offline Gmail and client applications, and using POP3 vs. IMAP access. Plus we set up our desired method. Now you can check other lab projects available for Gmail—just see the Labs tab in your account settings.
Eric Geier is an author of many computing and networking books, including Home Networking All-in-One Desk Reference For Dummies (Wiley 2008) and 100 Things You Need to Know about Microsoft Windows Vista (Que 2007).