Hello Samson54,

• Does the error occur repeatedly every time you launch NX4?
• Try rebooting XP and try it again.
• Try uninstalling NX4 and the reinstalling.
• Pay close attention to any messages that may appear during the install.
• What are your hardware specs (grapphics card, RAM, free disk space, etc.) and do they match the recommended system requirements for NX4?

Please report back.

Thanks and good luck.
3DCADTips Help Desk