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files, and consequent confusion by the user of cleaner products. There is little competent information about this specific interaction, and no integration. In general, even if
Registry cleaners could be arguably considered safe in a normal end-user environment, they should be avoided in an application virtualisation environment.
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program to know whether any particular key is invalid or redundant. A poorly designed
Registry cleaner may not be equipped to know for sure whether a key is still being used by Windows or what detrimental effects removing it may have. This may lead to loss of functionality and/or system instability,
123:
Due to the sheer size and complexity of the
Registry database, manually cleaning up redundant and invalid entries may be impractical, so Registry cleaners try to automate the process of looking for invalid entries, missing file references or broken links within the Registry and resolving or removing
353:
since all
Registry entries in this scenario are written to an application-specific virtual Registry instead of the real one. Complications of detailed interactions of real-mode with virtual also leaves the potential for incorrect removal of shortcuts and Registry entries that point to "disappeared"
226:
filed a lawsuit against two Texas firms, Branch
Software and Alpha Red, producers of the "Registry Cleaner XP" scareware. The lawsuit alleges that the company sent incessant pop-ups resembling system warnings to consumers' personal computers stating "CRITICAL ERROR MESSAGE! - REGISTRY DAMAGED AND
193:
or free downloads that falsely report problems that can be "rectified" by purchasing or downloading a
Registry cleaner. The worst of the breed are products that advertise and encourage a "free" Registry scan; however, the user typically finds the product has to be purchased for a substantial sum,
136:
Some
Registry cleaners make no distinction as to the severity of the errors, and many that do may erroneously categorize errors as "critical" with little basis to support it. Removing or changing certain Registry data can prevent the system from starting, or cause application errors and crashes.
127:
The correction of an invalid
Registry key (such as one or more that remain after uninstallation of a program application) can provide some benefits; but the most voluminous will usually be quite harmless, obsolete records linked with COM-based applications whose associated files are no longer
41:
Registry cleaners seem to no longer be supported by
Microsoft, despite originally having made and distributed their own registry cleaner under the name of RegClean. Currently, vendors of registry cleaners claim that they are useful to repair inconsistencies arising from manual changes to
255:. Furthermore, versions of Windows prior to Server 2003 may fail to start up if the Registry and kernel files are unable to fit within the first 16 MB of memory. Slowdown due to Registry bloat is thus far less of an issue in modern versions of Windows.
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The use of any registry cleaner can be detrimental to a machine, and there is never a good reason to ‘clean’ a registry. It is not a source of load or lag on a system in any way and can lead to additional problems such as software not working or even
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These tools are also difficult to manage in a non-boot situation, or during an infestation, compared to a full system restore from a backup. In the age of rapidly evolving malware, even a full system restore may be unable to remove a
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Most
Registry cleaners cannot repair scenarios such as undeletable Registry keys caused by embedded null characters in their names; only specialized tools such as the RegDelNull utility (part of the free
210:
Rogue Registry cleaners are often marketed with alarmist advertisements that falsely claim to have reanalysed your PC, displaying bogus warnings to take "corrective" action; hence the descriptive label
273:
The Windows Performance Toolkit is specifically designed to troubleshoot performance-related issues under Windows, and it does not include Registry cleaning as one of its optimizations.
439:
461:"The .NET Framework 2.0 SP1 installation fails on a computer that has the .NET Framework 2.0 installed and that is running Windows XP, Windows Server 2003, or Windows 2000"
407:
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tool), rather than attempting to clean the Registry's contents, has a measurable benefit and has therefore been recommended in the past by experts such as
829:
383:
309:). "Last known-good" restores the last system Registry hive (containing driver and service configuration) that successfully booted the system.
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computers, it was possible that a very large Registry could slow down the computer's start-up time. However, this is less of an issue with
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Registry cleaners are likewise not designed for malware removal, although minor side-effects can be repaired, such as a turned-off
824:
92:
186:
202:" including Registry cleaners has been ranked as one of the most prevalent pieces of malware currently in circulation.
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350:
486:"OL2000: Error Message: "Outlook Caused an Invalid Page Fault in Module Msvcrt.dll" When Creating an Appointment"
302:
550:"How do I uninstall Office 2003, Office 2007 or Office 2010 suites if I cannot uninstall it from Control Panel?"
49:
The effectiveness of Registry cleaners is a controversial topic. The issue is further clouded by the fact that
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CORRUPTED", before instructing users to visit a web site to download Registry Cleaner XP at a cost of $ 39.95.
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that cannot be mounted by the system, making the repair via "slave mounting" of a system disk impossible.
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666:"Windows 2000 Registry: Latest Features and APIs Provide the Power to Customize and Extend Your Apps"
432:"Error: "Internet Explorer Script Error..." when scanning after running a Registry cleanup utility"
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A corrupt Registry can be recovered in a number of ways that are supported by Microsoft (e.g.
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595:"Fright Fight: Washington Attorney General leading battle against scareware with Microsoft"
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251:), due to a different on-disk structure of the Registry, improved memory management, and
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511:"August 2009 Windows Vista and Windows Server 2008 Application Compatibility Update"
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687:"System may not start when creating a large number of logical units and volumes"
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A Registry cleaner is of no use for cleaning Registry entries associated with a
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the underlying Registry files (e.g. using the free Microsoft-supported
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95: in this section. Unsourced material may be challenged and removed.
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384:"Microsoft now detects CCleaner as a Potentially Unwanted Application"
305:, from a "last known-good" boot menu, by re-running setup or by using
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are involved, the removal of system-critical files may result.
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Registry cleaners have been used as a vehicle by a number of
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before it will effect any of the anticipated "repairs". The
798:"Getting Started with Microsoft Application Virtualization"
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from Microsoft to block problematic Registry cleaners. The
16:
Third-party utility to clean up Microsoft Windows Registry
329:. However, in complex scenarios where malware such as
34:, whose purpose is to remove redundant items from the
774:Bryce Cogswell and Mark Russinovich (2006-11-01).
57:are often associated with utilities of this type.
536:"Free Utility: Windows Installer CleanUp Utility"
153:was a Microsoft-supported utility for addressing
8:
401:"Symantec Report on Rogue Security Software"
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111:Learn how and when to remove this message
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406:. Symantec. 2009-10-28. Archived from
7:
732:"Windows Performance Analysis Tools"
243:-based operating systems (including
93:adding citations to reliable sources
642:"Fighting the scourge of scareware"
597:(Press release). Attorney General,
294:A Registry cleaner cannot repair a
14:
830:Windows-only proprietary software
438:. October 2, 2002. Archived from
151:Windows Installer CleanUp Utility
147:application compatibility updates
708:Lance Whitney (September 2007).
140:It is not always possible for a
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753:Mark Russinovich (2006-11-01).
290:Recovery capability limitations
286:software) are able to do this.
165:failing to work, if a registry
80:needs additional citations for
710:"Utility Spotlight PageDefrag"
231:Metrics of performance benefit
1:
640:Shiels, Maggie (2008-10-01).
61:Advantages and disadvantages
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345:Application virtualisation
303:Automated System Recovery
277:Undeletable registry keys
189:attacks that use website
42:applications, especially
181:applications to install
169:has not been performed.
776:"RootkitRevealer v1.71"
552:. Microsoft. 2010-06-29
351:virtualised application
196:rogue security software
825:Utility software types
691:support.microsoft.com
571:"Windows Maintenance"
206:Scanners as scareware
215:". In October 2008,
185:, typically through
89:improve this article
442:on December 7, 2008
322:from a hard drive.
575:r/TechSupport Wiki
492:. November 5, 2003
187:social engineering
755:"RegDelNull v1.1"
622:. StopBadware.Org
155:Windows Installer
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46:-based programs.
29:Microsoft Windows
27:designed for the
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268:Mark Russinovich
224:attorney general
173:Malware payloads
157:related issues.
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36:Windows Registry
32:operating system
25:utility software
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23:is a class of
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101:December 2014
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802:. Retrieved
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780:. Retrieved
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758:. Retrieved
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736:. Retrieved
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714:. Retrieved
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695:the original
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669:. Retrieved
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649:. Retrieved
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624:. Retrieved
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603:. Retrieved
601:. 2008-09-29
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578:. Retrieved
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554:. Retrieved
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538:. Microsoft.
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519:. Retrieved
517:. 2009-09-01
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494:. Retrieved
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469:. Retrieved
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444:. Retrieved
440:the original
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415:. Retrieved
408:the original
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284:Sysinternals
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258:Conversely,
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87:Please help
82:verification
79:
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800:. Microsoft
778:. Microsoft
734:. Microsoft
712:. Microsoft
145:As well as
142:third-party
819:Categories
804:2009-01-06
782:2008-12-08
760:2008-12-08
716:August 29,
651:2008-10-02
626:2008-06-21
620:"WinFixer"
605:2010-04-01
599:Washington
580:2024-04-24
556:2010-09-23
521:2009-09-25
496:2008-05-19
471:2008-05-19
446:2008-05-19
417:2010-04-15
370:References
264:PageDefrag
245:Windows XP
237:Windows 9x
221:Washington
191:pop-up ads
738:August 8,
515:Microsoft
490:Microsoft
465:Microsoft
217:Microsoft
213:scareware
128:present.
55:scareware
671:July 19,
646:BBC News
436:Symantec
358:See also
253:indexing
219:and the
200:WinFixer
339:viruses
331:spyware
320:rootkit
183:malware
163:Windows
51:malware
337:, and
335:adware
179:trojan
167:backup
124:them.
411:(PDF)
404:(PDF)
249:Vista
740:2010
718:2008
673:2007
247:and
53:and
235:On
91:by
44:COM
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689:.
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392:^
333:,
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241:NT
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19:A
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
