The Maintenance and Security Center (MSC) can be used to both verify and repair 4D databases.

In particular you can verify either the data file (.4DD) or the index file (.4DINDx), or both.

If 4D crashes or quits in some unexpected way it is common practice to run a verification to make sure nothing was damaged. Some users may opt to run a repair as well.

The tip in this case is that if you plan to run a repair anyway, you may as well skip the index verification to save yourself some time. Here's why:

• When you repair a data file, 4D moves the current data file and index file into a backup folder (called "Replaced Files (Repairing)" with a timestamp).
  
• The MSC then rebuilds the data file.
  
• That's it: a new index file does not yet exist.
  
• When you launch the repaired database in 4D the new index file is created at that time.

The point is, a Repair operation really doesn't repair the index file at all. It just removes it. So there's no reason to verify the old index file since 4D is going to create a new one anyway.