We seem to be getting quite a bit of inquiries lately regarding this msscipt.ocx related error message when working with pipe networks. It is not limited to Civil 3D and also manifests itself in AutoCAD MEP.
This is a Microsoft file and error caused by the file, that has little to do with Civil 3D and Autodesk products. In the research I have done I have found that apparently this file affects the ability for applications to work with XML files. A quick search on the internet reveals this file affects a number of different scenarios outside of Autodesk products.
The following is a typical list of suggestions we offer to users who have encountered this issue:
Install the script control: http://support.microsoft.com/kb/184739
The version of Internet Explorer (IE) 7, IE8, and IE9 may be preventing it from operating, you could try to uninstall it and reinstall it.
Try these steps:
1. Go to Start All Programs Accessories.
2. Right-click Command Prompt and choose "Run as administrator."
3. Enter the command: Regsvr32 C:\Windows\SysWOW64\msscript.ocx You can copy and paste this by right-clicking in the command prompt window to do the paste.
4. Click OK on the message that says the file registration succeeded.
5. On the keyboard, hold down the WINDOWS key and then hit R.
6. In the Run window, type REGEDIT and then click OK.
7. Find the following folder: HKEY_CLASSES_ROOT\TypeLib\(0E59F1D2-1FBE-11D0-8FF2-00A0D10038BC)\1.0\0\win32
8. Right-click the win32 folder and choose "Permissions."
9. Make sure the administrator group has full control.
10. With the win32 folder selected, make sure the (Default) key at the right is set to the following path with no quotes around it: C:\Windows\SysWOW64\msscript.ocx
11. Close the Registry Editor.
If you are lucky, one of these suggestions will resolve the issue and the msscript.ocx error will go away. However I have noticed that some users may need to resort to an operating system reinstall in order to rectify the issue.