Not sure if this will help anybody but I'm documenting my first upgrade to the "latest" OS: BlackBerry Device Software v4.5 (updated 10/31/2008)

Step One,
Check and download latest Blackberry desktop software at: https://www.blackberry.com/Downloads...93E4F3BB068C22

Step Two,
Select "Application Loader", and then "Update Software"

Step Three,
From there, the Blackberry Desktop software will check to see if you already have the latest OS update. If you don't, you'll be prompted to download the latest version.

WARNING. Do not interrupt installation of the OS. I received a 507 error because I hit the cancel button during the installation process. 2 hours later and a complete reinstall and system restore, I'm back in business.

With OS 4.5, you're supposed to receive and view HTML emails, but you have to enable this option first. This must be done through the online email setup at: https://bis.na.blackberry.com/html?brand=vzw for Verizon users. For all other users, go here to find your provider: http://na.blackberry.com/eng/support...#tab_tab_email

Update: I'm still unable to update my email settings to receive html emails. https://bis.na.blackberry.com/html?brand=vzw is down right now and there is no explanation as to why or if there's maintenance going on.