Many messaging apps on S60 (and other platforms as well, but this little tip is written with S60 in mind,) use ‘heartbeats’ to check e-mail. The way it works is sort of like this:

  • Phone: Hey, server, any mail for me?
  • Server: Nope.
  • Phone: OK, well, holler when there is, alright? I’ll check back in 10 minutes.
  • Server: Yup.


This idea works out fine, because now no more data needs to be sent unless a message actually arrives, which means your data connection can go idle, which means better battery life. The problem is what happens if some gremlins come along and break your network connectivity. You see, if you lose network connectivity one minute after that exchange above, if you get new mail, the server keeps trying to push it to you for 9 minutes, not knowing that your phone isn’t getting it.

Your phone doesn’t realize it’s lost network connectivity (because it’s expecting the server to push it the message) and so sits there, most likely with a dumb grin on its face, waiting for the 10 minutes to elapse. Then, it asks the server for mail, the server basically responds with “finally!” and sends the messages along and you’re back in sync.