We are aware that a variety of players are currently encountering a blank message box during the client startup, and work towards a resolution.
Before opening a new ticket, make sure that you have already checked the following:
Graphics Card Driver Clean Installation
Make sure that you have the latest version available for your model installed via a Clean Install (fully uninstall the previous version and reinstall using your vendor's software Clean Install option).
Alternatively, if that doesn't resolve the problem, try installing the previous stable version you were using.
Perform a client repair process, as described here.
Still have the issue?
Open a new ticket through our Customer Support portal and one of our GMs will get back to you as soon as possible; make sure to include your latest Client log files located inside your Log folder (installation directory).