It could be a permission problem. LaTale requires administrator privileges to run its X-Trap anti-hacking app.
Here are a couple of things you could try that could get your game working again:
First of all, you need either to log onto an administrator account, or you need to have the login information of an administrator account ready. You cannot run LaTale without being in administrator mode.
1: Start the OGP Launcher with administrator privileges. I'm not sure how different it is in Vista, but you can start a program in administrator mode by either right-clicking the shortcut and selecting an option along with the lines of "Run as administrator", or you can Right click the shortcut > Properties > Compatibility tab > check the box that says something like "Run as administrator." so that it goes into administrator mode every time you use the launcher.
2: Try disabling User Account Control (UAC). It's possible that UAC, a system that helps protect your computer by only using administrator privileges when it needs to, isn't giving the OGP Launcher the administrator privileges it needs to bring up LaTale. After doing so, you'll need to log on as an administrator to launch the game.