[Gladsomebeast]

Delta3D is an OSG based tool. I remember that their installer adds the Delta3D bin/dll directory to the PATH variable. This is probably causing the problem.

You can remove the Delta3D entry from the PATH environment variable by right clicking on My Computer->Properties->Advanced Tab->Environment Variables Button.

Under System Variables, select the Path variable, click edit, then remove the Delta3D entry. If you have problems with this, search google for guides on changing the Path Environment Variables with pictures.

Changing the Path will break Delta3D I assume though.