My Vault has lost the customisations that I made to the grid view. I have lost my custom Columns etc.
The individual user settings for the Vault "Grid views" are stored in an XML file in the following location on each PC.
C:\Users\[username]\AppData\Roaming\Autodesk\Autodesk Vault [Edition] [Product year]\Servers\[servername]\Vaults \[Vaultname]\Objects\GridState.xml
To save the current Grid State, simply log out of Vault and close it down. This will save the current settings to the XML file. You can make a backup of the users settings, and even lock write access to the file to prevent it being edited or deleted. You can copy this XML to other PC's too if you want the same settings on multiple machines.