Occasionally a user enters illegal characters into Alpha or Text fields. These characters may be control characters, high ASCII characters, or other characters that are not permitted in the field. Some of these characters appear as blank spaces, but others are invisible and nothing indicates that such a character has been entered.
In some cases, queries and sorts can cease working properly and indexes can become damaged.
This technical note offers a tool that allows you to purge indexed Alpha fields that may be used for queries and sorts.
The best way to avoid the problem is to use a data entry filter such as &"a-z;A-Z;0-9; ;,;.;:;é;è;ç;ù;à;-;/;" modified to meet your specific needs.