Files Delphi

Title: Resolving Primary key property is invalid... Error in DBF File
Question: Is your DBF file inaccessible and unusable? Are you unable to open the DBF file and extract stored data from it? This problem generally occurs due to corrupt index of DBF file.
Answer:
Is your DBF file inaccessible and unusable? Are you unable to open the DBF file and extract stored data from it? This problem generally occurs due to corrupt index of DBF file. The DBF file index may be corrupt because of numerous reasons, such as application malfunction and improper system shutdown. In FoxPro 2.6 and earlier versions, you can fix such problems by simply erasing IDX/CDX files and re-creating them. But, in Visual FoxPro, you cannot do this and face critical data loss problem. In order to extract your precious data from DBF file in such cases, DBF Recovery is the best way to go for.
Under Visual FoxPro environment, you cannot remove the CDX file once the DBF file table is bound to the database and has Primary index. If you try to remove the CDX file in such scenarios, you receive the following error message:
Primary key property is invalid, please validate database
The above error occurs while opening the DBF file table again in Visual FoxPro database. Furthermore, you encounter the below error message while re-creating an index on a removed CDX file, which has only candidate, unique, regular index:
Invalid database - please validate database
Cause:
You may come across this behavior of Visual FoxPro database due to corrupt index or corrupt DBF files. Corruption can be the outcome of various reasons, including virus infection, improper system shutdown, application crash, file system errors, hard drive I/O errors, and more.
Resolution:
Try out the below methods to Repair DBF File and fix this problem:
Use GenDBC.prg utility to re-create the Visual FoxPro database structure and the database indexes. After that, restore data back to every table.
Restore corrupted index files using the below steps:
Create a database table and table's indexes. Bind the table to
database.
Backup CDX file of newly created table.
Copy backup CDX file to the damaged CDX file of the table.
Open Visual FoxPro table and run Reindex command.
If you are still facing the same problem, use DBF file repair software to repair and restore the corrupt DBF file. The applications repair DBF database in a quick, safe, and easy manner using read-only algorithms and interactive graphical user interface.
Stellar Phoenix DBF Recovery is a result-oriented utility to effectively handle all DBF file corruption situations. The software works well with Visual FoxPro 6.0 to 9.0 and dBase III to V. It restores all corrupt objects of DBF file such as index, primary key, column data type, table name, and column name.