I have a departments table, and when I open it in browse mode, and type the following:
BROWSE FOR vehdept = 'PATROL'
It pulls up a single record, which has .NULL. in the vehdept field. There are other records with .NULL. in that field, but it only pulls up this one. ? IsnNull(VehDept) returns .t., so it's not a case of a string ".NULL." (Which shouldn't match either.)
If the record doesn't appear with
BROWSE FOR vehdept = 'PATROL' NOOPTIMIZE
then it's a corrupt index file.