I made the mistake of installing Yahoo! Go on my Pearl and it was a waste of time. According to Yahoo! support, some files were left behind by a previous version that are locked and cannot be deleted when Yahoo! Go is deleted. I already removed Yahoo! Go but now I want to be sure there are no files left behind on my BlackBerry. I would like to do a clean reinstall of the device software at the same time as I install the latest software from Rogers. I only have a few third-party applications on my device that I can easily reinstall. Is this simply a matter of not doing backup before I upgrade the software?

Before you do resinstall, what makes you think pieces are left behind?

Sometimes an uninstall will leave a module and you'll see, for example, the icon even after the application delete. If something like that is the case, simply go to options > advanced options > applications > modules and delete the yahoo go module.

Otherwise, see blackberryfaq.com for instruction on reinstalling the OS.

Here is link: Main Page - BlackBerryFAQ.com

I'm basing that on what Yahoo! support told me. They said that based on the symptoms of Y! Go (wouldn't update RSS feeds or stocks properly), there were locked files on the device that could only be removed by reinstalling the device software. I had tried to use the desktop software to remove the application but that didn't work, supposedly due to "locked files" according to Yahoo! support.

I've reinstalled the device software a few times before, but applications and other files are preserved (or maybe just restored) so I want to be sure the device is clean and that no junk files get put back.

Use the instructions in the faq to wipe the device and reinstall the OS if you really feel the need. I'll say I'm surprised, though. My understanding is deleting an application in options on the blackberry removes everything, but don't hold me to it.

I would have thought the same thing, but even after deleting and reinstalling the application, it was showing data that I had entered previously (e.g., stock portfolios). Yahoo! support told me the files were locked and they couldn't be deleted.

Wirelessly posted (8700g: BlackBerry8700/4.2.1 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/100)

I wouldn't know whether that data was from the blackberry from a previous install, or data from yahoo's servers uploaded from a previous install and redownloaded with the new install. Just academic to me, though. Have you done the OS reinstall? If so, did it go ok?

Just did the install. I wanted to get the phone as clean as possible so I deleted all applications and application data before installing the device software, including some themes I had downloaded and also the daylight savings time patch. When I installed the device software, I selected the option to not do a backup beforehand. It took the usual 45 minutes or so then came back up as a pristine new BlackBerry. I went through the setup wizard and once it initialized all of the data, it's working fine. It did manage to find some data because some of my brower links were preserved. It also remembered my bluetooth devices. Not sure where it found that information if the data was not restored.

One small gotcha, however. I went to the blackberry website to download the Dimension Today Plus theme and it's not there! The website says there are no themes for my version of software. Anyone know if the Dimension Today Plus theme is available from anywhere else or why it wouldn't be available on the blackberry website? I really like that theme and would like to get it back on my phone. Is it possible to selectively restore it from a previous backup?

Themes aren't backed up during a normal backup. If you upgraded the OS then that's why the theme is no longer available. Not all themes are available for all OS's and/or devices.

The Dimension Today Plus theme was from the BlackBerry Website, along with the Phantom theme that I never used. They weren't part of the OS, but showed up as additional applications.

Right. I'm familiar with it. However, if you upgraded the OS to a newer version then those themes may not be compatible and therefore won't be download-able anymore.