I've been having this issue since the open beta. Everything is just fine the first time I install PSO2, but after closing it the first time and attempting to launch it again, I get an error message:

"Windows cannot access the specified device, path or file. You may not have the appropriate permissions to access the item."

I've tried running it as an admin. Both deleting the PSO2 program folder and properly uninstalling the game, then reinstalling it make everything work just fine again; until I close the launcher or game, at which point I run into the same issue.

pso2launcher.exe, pso2updater.exe, and pso2download.exe in the bin folder don't have teir own icons anymore, if that helps.