The error message you are seeing is from an older version of MacCheck. It is actually giving you more detail than is necessary, or helpful. It refers to an index in the catalog tree.
We believe that error message may result from a problem in MacCheck version 1.0.3. Release 1.0.4 of MacCheck actually incorporates some Disk First Aid
code, and would not give these messages. It doesn't sound like there is an actual problem with your system because Disk First Aid would have flagged a problem.
MacCheck v1.0.5 was the last version of MacCheck to be released.
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