To be able to access Gmail account offline, you’ll need to first download and instal Google Gears. If you’re using Google’s Chrome browser, though, you can relax since Chrome comes with Gears installed by default.
So i Personally say that you used google chrome if you want to access offline gmail in good way...
How To Create Shortcut For Offline Gmail
1)) go to Settings->Labs and enable the Offline feature.
2))Gmail should now reload and you will see a new link titled “Offline“ right next to the “Settings“ link in the top right corner of the Gmail window.
3))Click on Offline and Google Gears will throw a warning at you that some website named http://mail.google.com/ trying to access Gears. Since I was quite sure that it’d harmless, I let the website access Gears and you should probably do the same.now begin downloading what it thinks are the most important emails to you. I’m saying “what it thinks” because the Gmail team has a pretty nifty algorithm to determine the emails that it downloads. For me that figure came to “about 4 years” worth of my emails and you might get a different figure, depending on the amount of email that you get.
At any rate, Gears will download about 10000 of your latest emails, not counting the Trash and Spam folder so this should be enough for most of us.
Depending on the speed of your link, this actual process of downloading and syncing emails might take a while...
4))Gears will also offer to create a shortcut for Gmail on the desktop. With this shortcut, you can login Gmail in offline mode right from your desktop.
The Offline Gmail feature also includes a very cool Flaky Connection Mode. In this mode, you can continue using Gmail as you normally would and Gmail will automatically determine if you are online or offline, without the user ever knowing about it.
If you send any emails in this mode and you’re offline, Gmail will keep them in the outbox and send them as soon as you come back online, and you’ll never even come to know about your connection status. In my opinion, you should always keep this option checked. To enable the flaky connection mode, click on the Offline Gmail icon next to the Settings link.