As I’ve mentioned before, Softimage cannot run without VBScript. You won’t get any errors with xsi.exe, just a crash, usually sometime after the splash screen. But xsibatch will give you some errors that tell you what the problem is:

C:\Program Files\Autodesk\Softimage 2013\Application\bin>xsibatch -processing -script %TEST%\test.vbs
======================================================
Autodesk Softimage 11.0.525.0
======================================================

ERROR : 2000 - Failed creating scripting engine: VBScript.
ERROR : 2000 - Failed creating scripting engine: JScript.

It turns out the problem is related to McAfee antivirus, which for some reason has overwritten some important VBScript and JScript registry values.

To fix this, you need to get back the VBScript and JScript registry entries. I haven’t had to do this myself, but I think this page gives a good explanation of the problem and what to do:
http://windowsexplored.com/2012/01/04/the-case-of-the-disabled-script-engines/

You’ll find a number of other pages on the Web about this. For example, here’s a thread on sevenforums.com. Note that fixing just VBScript is probably sufficient to get Softimage to start, but you’d still be missing JScript.

Related post: The case of the missing vbscript