In general, the occurrence of errors in a system's Registry increases over time and with the Registry's continued growth.This is because the most common and abundant errors are orphaned Registry entries created during the installation or incomplete removal of registered applications and hardware drivers, making them largely responsible for the overall degradation of database stability as the Registry is forced to grow around them.
These errors usually have a minimal affect on overall system performance, but can become debilitating if they are left in the registry for a very long time or if the Registry grows very rapidly. In a sense, your system is doomed from the start.
If you add to these odds your Registry's chances of escaping all other sources and types of errors completely, it will probably become apparent that something needs to be done.
What's to be done?
It is almost universally decided that incorporating a regular Windows Registry Repair and Maintenance Program into your Registry's diet will not only prevent system crashes by repairing major registry issues, but will also maintain a more stable database structure by periodically removing the multitude of minor errors that are responsible for its gradual degradation over time as it grows around them.
Registry Repair Utilities
Although some versions of Windows provide built-in background system utilities designed to maintain Registry structure and stability, these utilities only address the most basic Registry problems in the most primitive ways, making them insufficient when a Registry becomes really huge and complicated.
Fortunately, there are currently an infinite number of third-party Windows Registry repair utilities available on the Internet, spanning the full spectrum in cost user control that are effective in removing a large number of common Registry errors.
Combination Repair and Cleaning utilities fix errors caused by invalid references, viruses, and spyware and tracking programs, as well as defragment hives and backup/restore registry data.
The most common errors addressed by these utilities are :
- Orphaned, missing, obsolete and damaged Registry keys, These are usually caused by applications that are incompletely or incorrectly uninstalled.
- Orphaned DLLs (Dynamic Link Libraries). These are invalid registry entries in the SharedDDLs section that are created when a DLL shared by multiple applications is deleted or moved.
- Missing or corrupt GUIDs (Globally-unique Identifiers), The registered components that are identified by the Registry by GUIDs rather than their paths and filenames can no longer function..
- File Not Found errors
- Old or corrupted hardware drivers
- Registry fragmentation, Fragmentation of registry hives occurs when applications repeatedly modify the same values in small increments.
- Virus and spyware that enter the registry by creating or modifying keys.
How often you should use these utilities depends on your Registry's size and your system's activity and can be best determined by starting off with a very frequent repair schedule, slowly increasing the time between successive repair. Source
