It sounds like index corruption to me. The only way to verify that is to re-index the table.

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>I have free table with an index. In the index are a lot of different keys.
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>I just had a problem where most of the keys in the index disappeared.
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> The index didn't appear corrupted and the file could still be accessed.
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>Anyone seen anything like that before or suggest a cause?
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>The table is accessed via forms in the application and also by some scheduled programs.
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>Thanks
>
>Nick