Weird...found the arcitle below on the Windows issue:
https://www.symantec.com/connect/blogs/ds-7x-error-handle-invalid-when-running-scripted-os-installation-soi
Might also be worth your while reading the forum query below (ex-the Windows issue):
https://www.symantec.com/connect/forums/altiris-75-unable-create-windows-7-ent-x64-image
Is these don't resolve it, then consider logging a call with Symantec.Just post back with a solution.
Thanks!