[dtndvm]

I had a similar problem on my Mogul last year. Somehow, when I did an install, it wasn't completing the install so Opera kept starting it over. I fixed it by uninstalling, soft resetting, then installing it again.
Look at your versions also and see what Opera version is installed and then see what is trying to install. If its always trying to install a different version, then the install isn't completing fully. If it keeps trying to install the same version, something is corrupted and you probable need to start fresh. You may also want to download a new copy direct from Opera in case the install package itself is corrupted.