B. Make sure the index has been updated, if any edits have been performed to the reference data. This can be done by running the 'Rebuilding geocoding indexes' tool in ArcToolbox. - Rebuild geocoding indexes.
C. Make sure the address being searched for has been posted into the default version, and that the database has been compressed. -Compress a Geodatabase.
A. Delete the existing index, just the index, not the address locator, and create a new one using the 'Rebuild Geocoding Indexes' tool. See step 1A above to determine which geocoding index corresponds to which locator.
B. Make sure that the Address Locator is not in use by another application.
C. Make sure that you are the owner of the Address Locator.
Problem: Experiencing Slow Performance:
A. Make sure that the geocoding index is up-to-date by rebuilding it. See step 1B above.
B. Versioned reference data is much slower than non-versioned data.
C. A geocoding service in ArcSDE may be faster than a geocoding service in ArcMap, or vice versa.
D. ArcGIS 9.0 and 9.1 are notoriously slow when geocoding in a Geodatabase; exporting the layers to a shapefile may speed things up immensely.
Problems while creating custom geocoding styles:
A. After the styles have been modified, they must be imported into ArcSDE. - Please see the ArcSDE Command Reference under 'sdegcdrules'.