Any doctor will subscribe to the adage Prevention is Key when it comes to illnesses. It is the same for an OS too. Trying to fix registry errors after they emerge is more problematic. So prevent them from emerging in the first place.
Windows registry errors specifically the ones pertinent to the in built applications and to Windows as well are very common and end up killing Registries. When one installs new applications, and uninstalls the old ones, the registry database witnesses changes even as remnants of the previously registered applications still exist here.
These registry errors are not problematic in a new system but if kept unchecked for long will increase the registry size and tamper with the structure and stability of its database. If your registry grows fast and the registry fix is not regularly done, its database can veer out of control, your system can crash and the OS speeds can be severely affected.
So how do you fix registry errors?
The Windows Operating System comes equipped with inbuilt system tools and utilities to uphold the existing registry structure and keep it stable. Know however, that these tools can only solve the most fundamental of Registry problems in rudimentary ways and generally fail to act when the registry bloats in size or becomes complex with the repeated addition and removal of programs.
There are some free registry fix utilities available on the Internet today. These are generally third party utilities but are very economical and versatile. They are user friendly and require little in terms of maintenance. The free registry fixes undertake both repair and cleaning of registries, eliminate errors, viruses and tracking programs, undertake the 'defrag', regular scans and backup your registry as well. These enable optimal performance of the OS and increase its life span.