Open the Registry Editor (regedit).
- Select: HKEY_CURRENT_USER\Software\Schneider Electric\Unity Pro XL\ProductVersion0\Context
- Delete ToolBars Key (folder).
Relaunch Unity Pro.

An alternative approach would be to turn off "Contextual Restore at Project opening" . This will allow Unity to open the project without any of the previous windows
automatically opening. You can find the option by selecting Tools/Options/General/Contextual Restore at Project Opening.