Change all data references from the Vault format to data shortcuts.
Autodesk
AutoCAD Civil 3D 2015
Data Shortcuts Editor.
Open Data Shortcuts Folder. In the Browse for Folder dialog box, browse to the folder for the project that you want to convert. The default location is C:\Civil 3D Projects. After you select the project folder, the Vault references are loaded into the table.
Find and Replace. Replace each instance of $ with the path to the local project folder (example: C:\Civil 3D Projects).
Save As, and then save the new Shortcuts folder in its current location.