The actual script path is "c:\script with spaces in the name.vbs"
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Here's the fix.
copy this code and paste it into a blank text file. Save it as whatever.reg and then double click on it to enter the contents into the registry:
Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\VBSFile\Shell\Open\Command]
@="C:\\WINDOWS\\system32\\WScript.exe \"%1\""