GreyMail provides a clean way of displaying new messages on your desktop, just like Microsoft Outlook™. Here's how to enable and test it.
First, ensure you are using Google Chrome. GreyMail utilizes Chrome extensions for this to work properly.
Second, log into GreyMail. Once logged in, go to Settings >> Preferences >> Mailbox View. You should see the following towards the bottom:
Now, check "Display Desktop Notification on New Message". Once you check this, hit "Test". A notice will popup on your browser. Click Allow.
You may also click the other options to enable even more notifications and sounds. You can play with them to see exactly how they work, just hit "Test".
Click Save below that, and you will now receive desktop notifications when you have new email!