Error Message:

Repairing an index entry in index name of file filename.

Explanation:

In an NTFS volume, directories are ordinary files with an index attribute assigned to them. It is the index attribute that allows the file to function as a directory. The name for index attribute for all directories is $I30. All files with an index attribute of $I30 contains a list of files and each file is referenced back to the index attribute by a File Record Segment (FRS) number. Each file in the Master File Table (MFT) has an FRS assigned to it. This message implies that the index attribute for the specified file is corrupted. That is, there is a directory out there (who's name we do not know) that had a file assigned to it with an FRS number of xxxxx and that file is no longer linked to the directory. Chkdsk found a corrupted directory and is assigning a new index attribute to the specified file. No user action required