The Windows registry is a central database of information needed to configure your computer system for general settings and preferences, software applications, and hardware drivers and devices. Keeping your registry in a good state of repair and conducting regular maintenance is imperative because the registry contains important data that is used all the time during system operation.

As you continue changing preferences, installing and uninstalling software and hardware, the registry grows and becomes more complex. In addition, the chances of errors and missing, obsolete or corrupt entries increases exponentially.

The registry is a centralised hierarchical database used by various versions of Windows (MS Windows 9x, CE, NT, 2000 and XP) to store computer configuration information. This information is necessary for Windows to run your computer system including all your installed applications and hardware devices. Not only does the registry save the path and location of these items, it also retains other details which help the processor to locate applications and hardware devices quickly and efficiently thereby reduce decreasing processing time. Records are kept of each and every item present

Registry entries include details on:

User profiles, settings, options and preferences
Applications installed on the computer
Property settings for folders and applications
Hardware devices installed on the system
Ports being used
System Policies
File Associations

Whenever you make any changes in your preferences or settings, installed software or hardware, these changes are stored in the Windows registry. Changes in your registry settings may be made by using the Registry Editor (regedit.exe) provided with Windows.

Beware any changes you may effect may cause errors in the Registry that could disable your computer.

Be extremely careful if you make changes or delete files from your registry – many times you will not be able to identify redundant files and may inadvertently delete a file needed to run your favourite program or your system software.

back to the top

When and Why do Registry Problems occur?

The latest statistics show that about 94% of computers have corrupt and possibly harmful files. On average, almost each PC will have about 150+ errors on them due to corrupt or missing registry entries.

If your system is new, you usually will not notice the need to effect any changes to your registry. However, over time, your registry will grow as you add and remove software and hardware on your computer. These additions and deletions will cause your Windows registry to become fragmented, corrupted or full of errors.

Common errors include:

Missing, orphaned, broken or bad application/Windows paths, shortcuts and links,
Unwanted browser objects,
Unused, obsolete Start Menu items,
Missing or corrupt application IDs,
Corrupt Active X/COM Objects,
Residual and unused file and drivers,
Unnecessary recent files list…
…the list is endless.

When you remove software from your system, for example, it is highly probable that residuals are still littering your hard drive and your registry. The result? Frequent error messages, slow start-ups, sluggishness, declining performance, system stalls, severe degradation in operating speed, unstable and frequent application errors and crashes, and, at times, even an inability to start Windows.

More often than not, these problems happen because:

You install or uninstall applications including trial downloads.
Some programmes are never really completely uninstalled leaving hard-to-find traces in your Windows registry.
You have embedded spyware, adware or other components (such as DLLs or programmes that revive themselves on every start up.
You have unused but undeleted drivers within your system.
It is critical to have a healthy and clean Registry for optimum system performance and system stability. Registry entries should not be left to stagnate in your system where they may eventually cause problems.
Keeping track of all this information is gruelling and bewildering – it’s not an easy job.

back to the top

How is the Windows Registry Structured?

The registry database is stored in a hierarchical structure as may be seen from the screen shot below. It may be best to conceive the registry as a tree divided into a number of areas or branches. Depending on your Windows version, the Registry comprises four to six sub-trees of keys called hives (also referred to as discrete files).

Each hive contains a Registry sub-tree, which has a key that serves as the root (i.e., starting point) of the tree. A registry hive is a group of keys, subkeys, and values in the registry that has a set of supporting files containing backups of its data. Subkeys and their values reside beneath the root. The values contain the actual information stored in the Registry.

The majority of the information in the Registry is placed there automatically by Windows when the operating system is installed. The rest comes from applications and hardware via installation routines.

It is also possible to edit Registry data manually, allowing you to tweak, enable or fix certain settings.

Any changes you make to the registry using Registry Editor are permanent, there is no “undo” button, so be very careful what you do.

Only edit the registry if you know what you are doing: the consequences of your mistakes could be rather extreme - at its worst, you will need to re-install Windows from scratch.

Edit at your own risk, and as a rule of thumb always make a backup.

The following screen-shots are taken from the Windows Registry Editor (type 'regedit.exe' at the Start Menu->Run prompt).

Folders represent keys in the registry (files represent hives) and are shown in the navigation area on the left side of the Registry Editor window. In the topic area on the right, the entries in a key are displayed. When you double-click a entry, it opens an editing dialog box.

As such, what you need to remember is that there are six root keys, each of which contains specific registry information:

HKEY_CLASSES_ROOT contains file associations and OLE information necessary to launch applications. Associations define what program runs when you double-click on a file name, what Context menu items appear when you right-click on the file. For example the root stores information about Active X controls, the names of all drivers, icons used for applications and documents, information supporting the drag-and-drop feature, all the extensions and the associations between applications and documents, shortcuts, COM sections and crucial features of the Windows user interface. The root key controls all the data files.
HKEY_CURRENT_USER contains the configuration information for the user who is currently logged on the machine. This portion of the registry links to the relevant area in the HKEY_USERS branch and cannot be edited.
The HKEY_USERS branch contains the profiles (including all the specific data) of all the users of the particular computer. This includes such items as screen savers, start menu settings and desktop preferences, fonts, event sounds, the recent start/run entries and folder view preferences for each user including default settings for new users.
HKEY_LOCAL_MACHINE has computer-specific configuration information used for all users who log onto computer. This key contains five-sub keys namely

Hardware (including the system hardware database generated during boot-up, all device drivers to be loaded, IRQ hooks and DMA settings and all resource allocations for each driver)
Security Accounts Manager (SAM) containing the user and group account database.
Security containing security policy information.
Software containing all configuration definitions and data for all software installed on the computer including the operating system. You will see sub-keys for each software title installed on the system.
System information.

HKEY_CURRENT_CONFIG contains all the relevant information relating to the hardware installed on the particular computer. This information is used by the computer at system start-up.
HKEY_DYN_DATA stores all plug and play information on the computer. Since this configuration information requires fast modification and retrieval by Windows, it is sent to RAM since the system cannot wait for the registry to send it to the hard drive. The information in this key is created afresh every time Windows is started and is thus dynamic also changing as devices are added and removed from the system.

Each registry value is stored as one of six main data types:

REG_BINARY: The data is in raw binary. Most of the information relating to hardware components is stored in this format and may be displayed by the Windows Registry Editor in hexadecimal format.
REG_DWORD this indicates that the data type is stored in a double word, always displayed as a four-byte number. Device drivers and services parameters are often of this type and can be viewed in binary, hexadecimal, or decimal using the Registry editor.
REG_EXPAND_SZ relates to a data string of variable length. This data type includes variables that are resolved when a program or service uses the data.
REG_MULTI_SZ is a multiple string. Values of this type of data usually contain list or multiple values that users are able to read.
REG_SZ relates to a fixed length text string.
REG_FULL_RESOURCE_DESCRIPTOR are used in hardware registry keys.

Other data types exist however these are not available through the standard registry editors.

Incorrectly editing the registry may severely damage your system. Before making changes to the registry, you should back up any valued data on your computer.

back to the top

How do I know whether I have Registry problems?

Changes are not necessary when you have a new system even though within a very short period, your registry will quickly grow as you install and remove software and hardware. Usually, within six months, your Windows Registry will become highly fragmented with regular use; and, if you add and remove software and hardware frequently or often effect changes within your system, your registry may corrupt and be full of errors.

Changes to registry entries modify the size of the files where the information is stored.

Registry fragmentation occurs because certain processes continually use the registry to incrementally modify the same values in the corresponding registry hives (see, How is Windows Registry Structured to learn what hives are). Microsoft warns, for example, that this fragmentation, in certain cases, may be excessive. File sizes may eventually exceed the Registry Size Limits imposed by Windows and this will cause subsequent modifications to the registry to fail with resultant errors, slowdowns and crashes.

Some registry errors include:

Missing, orphaned, broken or bad application/Windows paths, shortcuts and links,
Unused, obsolete Start Menu items,
Missing or corrupt application IDs,
Residual and unused files,
Unused and unwanted drivers,
…the list is endless (see, What are the most common Registry problems?).

None of these problems are visible unless you access the registry directly. And even there the problems are rarely obvious. Registry fragmentation and errors will effect the performance of your computer and its stability and smooth operation.

The more frequent symptoms of registry problems include:

Frequent error messages,
Slow start-ups,
Sluggishness,
Declining performance,
System stalls,
Severe degradation in operating speed,
Unstable and frequent application errors and crashes, and,
At times, even an inability to start Windows.

back to the top

What are the most common Registry problems?

Several problems may occur within your registry and are generally related to registry fragmentation, and corrupt, unused, missing, orphaned or obsolete entries.

Fragmentation may be a serious problem and usually occurs because certain processes continually and incrementally modify the same values within the registry. This fragmentation, in certain cases, be excessive and eventually registry file sizes may exceed the Registry Size Limits imposed by Windows. This will cause any subsequent modifications to the registry to fail.

Other registry errors include:

Registry integrity and shell folder entries including My Documents, profiles and favourites.
Software locations including missing, orphaned, broken or bad application/Windows paths, and links.
Unwanted browser objects.
Corrupt Active X/COM Objects.
Unused, obsolete Start Menu items.
Redundant Startup applications and uninstalled application schedulers.
Orphaned shortcuts, temporary (.tmp) files and Scandisk or Checkdisk fragment (.chk) files.
Missing or corrupt application IDs.
Obsolete shared DLLs and folders.
Unused help file references.
Residual and unused files.
Uninstalled software remnants.
Unused and unwanted drivers.
File extensions and associations.
Unnecessary fonts and recent files list.

back to the top

Is my PC free of Registry problems?

Statistics show that about 94% of computers have corrupt and possibly harmful files. On average, almost each PC will have about 150+ errors on them due to corrupt or missing registry entries.

Although a closer analysis is needed (download Registry Booster for a free scan), it is highly probable that even though your computer system is new or you are not encountering any visible serious problems, your computer already has some problems in the registry. The more frequent symptoms of registry problems include:

Frequent error messages,
Slow start-ups,
Sluggishness,
Declining performance,
System stalls,
Severe degradation in operating speed,
Unstable and frequent application errors and crashes, and,
At times, even an inability to start Windows.

If you are experiencing system crashes or if some of your installed applications are freezing or seizing for no obvious reason, your best bet is to defragment, clean and repair your Registry.

Incorrectly editing the registry may severely damage your system. Before making changes to the registry, you should back up any valued data on your computer.

This is why Registry Booster has become one of the leading registry repair software utilities on the market. Literally, hundreds of users entrust the defragging, cleaning and repairing to the Registry Booster, which, when used regularly, ensures that you prevent registry glitches and errors thereby dramatically improving system performance and stability.

Registry Booster is the safest and most trusted solution to clean and optimise your system, free it from errors and residual files and drivers. Through Advanced Error Detection Technology, Registry Booster automatically identifies missing, corrupt, or invalid entries in your Windows registry and dramatically enhance performance and stability.

With Registry Booster, you don't need to keep track of all the sources of common problems. One mouse-click and Registry Booster does the rest. And, using Registry Booster regularly keeps your PC free from errors and from unused or unwanted files.

Registry Booster is truly PC Repairs Made Easy!

back to the top

Do I need to repair Registry problems?

Without any shadow of doubt! If you don't, error messages will increase, your system start-up time will increase, your computer will be more sluggish then ever, system performance will take a nose-dive, you will start experiencing more frequent application seizures and crashes and eventually Windows may not start.

Prevention is always better than cure. Repairing registry issues and preventing crashes should be a your top priority - however, this means that you are reacting to problems as they arise. Instead, you should use registry repair software (such as Registry Booster) regularly (at least once a month) to clean your system and keep it operating at peak performance and stability. Defragging your registry is also crucial. Fragmentation may be a serious problem and usually occurs because certain processes continually and incrementally modify the same values within the registry. This fragmentation, in certain cases, be excessive and eventually registry file sizes may exceed the Registry Size Limits imposed by Windows. This will cause any subsequent modifications to the registry to fail.

back to the top

How do I repair Registry problems?

Registry problems may be repaired either manually by accessing the regedit utility built in Windows or automatically through registry repair software. The regedit utility is accessed through the Start Menu->Run and then typing regedit before clicking OK.

Keeping your system free of registry problems and fragmented entries is difficult even for the most experienced of users. The task is daunting and rather confusing simply because there are so many registry entries and detailed knowledge is required to effect any changes and not cause damage. Incorrectly editing the registry may severely damage your system. Before making changes to the registry, you should back up any valued data on your computer.

The top registry repair software solutions like Registry Booster help you do all this work automatically at the click of a button.

Simply click on the Start Scan button to scan your registry and identify problems. Once these problems are listed you can repair your registry with the click of the Repaid Registry button. To defrag your registry, just click on the relevant button.

back to the top

What is Registry Repair Software?

Registry repair software fixes all your registry problems including all errors and instances of fragmentation.

It tunes up and streamlines your computer registry to enhance your computer experience and eliminating related system seizures and crashes. Registry repair software keeps track of all registry entries repairing issues and ensuring your computer to work at peak performance. Using the software regularly allows you to minimise registry related problems (see, What are the most common Registry problems?).

Fragmentation is a serious problem and occurs when application processes modify the registry continually and incrementally . Eventually registry file sizes may exceed the Registry Size Limits imposed by Windows. This causes subsequent modifications to the registry to fail. Most registry repair software allow you to defrag your registry ensuring that such issues do not occur. This is true prevention.

Running registry repair software regular prevents registry errors and fragmentation thereby eliminating related system seizures and crashes.
Incorrectly editing the registry may severely damage your system. Before making changes to the registry, you should back up any valued data on your computer including your registry.

Although you can repair your registry (see, How do I repair Registry problems?) manually, this is not advisable. Registry repair without appropriate software requires a high degree of expertise. Even your decision on which software to use/buy must not be taken lightly. You wouldn't want to skimp on your software purchase. You must be careful: you could end up with removing critical registry entries and information that will damage your system and jeopardise its stable operation. This would mean spending more money to get costly computer repair and, most probably, recovering lost data (in certain instances this may not be even possible).

What's Next?

An Introduction to Registry Booster