The registry involves three main types of problems:
1. File integrity problems - registry files are damaged;
2. Database structure problems - the registry is a database organized in strict order. If the structure is dusturbed errors will arise while reading/writing to the registry;
3. Logical errors - discrepancy between records in the registry and actual system state. These errors cannot be found by the system and can lead to inexplicable crashes and error messages.
The first type of error can be fixed by disk scanning programs like scandisk and chkdsk.
The second type can be fixed in Windows® 98/MErunning "scanreg.exe /fix" command in DOS prompt. In Windows® NT/2000/XP/2003/Vistathese errors can be eliminated only by restoring registry files from a backup. Windows® includes System Backup & Restore utilities for this purpose.
The third type can be fixed by Registry Healer and utilities like this. While some utilities simply delete problem registry keys, Registry Healer searches the system for corrections and applies them.
Registry Healercannot help if the registry file integrity problems but can correct logical errors.
In case of file integrity problems, restore the registry to a previous backup point.