An electronic device, such as a hand-held portable computer, is provided with client-side email capability that allows emails to be independently downloaded from a server, regardless of an operating mode of an email application and without using the standard email retrieval mechanism of the email application. The emails are periodically downloaded without attachments in response to a poll of the server and if a sufficient high-speed connection to the server is available, and then the downloaded email is locally stored in a local cache of the portable computer. Attachments associated with downloaded emails stored in the local cache can be selectively downloaded, via a background process, from the server independently of the operating mode of the email application and during any suitable power state of the electronic device. Synchronization of attachments to emails in the local cache is also independently performed, thereby bypassing synchronization that is normally performed by the email application while in the online mode.