>>< SNIP >
>>
>>>But I will change the program to delete the indexes and recreate them on program start.
>>
>>Simetimes the header of the index file gets corrupted in such way that REINDEX cannot fix it.
>>
>>< SNIP >
>
>But I would expect there to be an error in this case, wouldn't you?

Unfortunatelly there is none but indexes're still corrupted after REINDEX in such case.