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INFO: RegClean 4.1a Description and General Issues

Last reviewed: October 5, 1998
Article ID: Q147769


The information in this article applies to:
  • Microsoft Windows 95
  • Microsoft Windows NT Workstation and NT Server, version 3.51 (SP 5) and higher
  • Microsoft Exchange, all versions
  • Microsoft Internet Explorer, version 3.0 and higher
  • Microsoft Office, all versions
  • Microsoft Outlook, all versions
  • Microsoft Word for Windows, all versions
  • Microsoft FrontPage, all versions
  • Microsoft Excel, all versions
  • Microsoft Access, all versions
  • Microsoft Visual C++, all versions
  • Microsoft Visual Basic, version 4.0 and higher
  • Microsoft Visual FoxPro, version 5.0a

SUMMARY

When you install, uninstall, and reinstall programs on your computer, registry keys are created, modified, or deleted. Over time, your computer's registry may begin to contain corrupted, unused, and unnecessary registry keys, especially if keys are not removed when you uninstall a program. As a result, you may begin to experience problems when using OLE to embed objects or Automation to control other programs.

The RegClean utility is designed to clean up unnecessary registry entries in your registry.

The RegClean utility that was originally supplied with Microsoft Visual Basic, version 4.0 for Windows. The Microsoft Office 97 Resource Kit has been updated. The current version is 4.1a.

MORE INFORMATION

How To Install RegClean

Copy version 4.1a build 7364.1 of RegClean.exe to any folder on your machine.

How To Run RegClean

  1. Double-click the RegClean icon. RegClean displays a progress dialog box. While the progress dialog box is shown, RegClean loads a copy of the parts of the registry that it is going to check and then performs the actual scanning. Depending on how much information is in the registry and the speed of your CPU, this will take anywhere from about 30 seconds to 30 minutes.

    If you have many entries in your registry, sometimes RegClean might appear to have stopped working. In fact, RegClean might appear completely halted whenever it is checking remote or removable drives.

  2. Once these progress meters have disappeared, you will be prompted for the next action. You can do two things at this point:

    - Exit RegClean. If RegClean did not find any errors in your registry

         or if you do not want RegClean to fix the errors that it found, click
         Cancel.
    
  • Allow RegClean to fix the errors that it found. Click Fix Errors to prompt RegClean to remove the entries containing errors that RegClean found in the registry. A progress meter is displayed while RegClean does this. Sometimes the progress meter stops momentarily, but it should resume after a few seconds. When the meter is gone, RegClean is done. Click Exit to end RegClean.

    Clicking Fix Errors also creates an Undo.reg file in the folder where you ran RegClean. The file will be titled “UNDO computer yyyymmddhhmmss.REG,” where computer is the name of your computer, yyyymmdd is the date, and hhmmss is the time. If at any point you would like to "undo" or put back what RegClean removed from your registry, double-click the Undo.reg file.

    The RegClean utility is available for downloading free of charge.

    The following file is available for download from the Microsoft Software Library:

     ~ RegClean.exe (size: 800136 bytes) 
    
    
    For more information about downloading files from the Microsoft Software Library, please see the following article in the Microsoft Knowledge Base:

      ARTICLE-ID: Q119591
      TITLE     : How to Obtain Microsoft Support Files from Online Services
    
    

    What RegClean Does

    RegClean analyzes Windows Registry keys that are stored in HKEY_CLASSES_ROOT in the Windows Registry. It finds keys that contain erroneous values, and after recording those entries in an Undo.reg file, it removes them from the Windows Registry.

    What RegClean Does Not Do

    RegClean does not fix every known problem with the registry. It does not fix a "corrupt" registry; it is limited to fixing problems with normal Windows Registry entries located in HKEY_CLASSES_ROOT.

    It is very possible that RegClean will not correct a problem that you have encountered. RegClean will leave any entries in the registry that it does not understand or that could possibly be correct.

    General Issues

    • Oleaut32.dll
    • Doesn't solve problems/makes new problems
    • Cannot undo the reg file

    FIX: REQUIRES UPDATED OLEAUT32

    This error occurred with an earlier version of RegClean. In order for RegClean to work, you must have the updated version of the OLEAUT32.dll. If your system has Internet Explorer version 2.0 or lower, installing Internet Explorer version 3.0 or higher will update the OLEAUT32.dll. If you are using Microsoft Windows NT 3.51 with SP 4 or lower, you will need to install SP 5 in order to update the OLEAUT32.dll. These files are also available for download below. If you experience the below symptoms when using RegClean 4.1a, please follow the resolution instructions.

    Symptoms

    Two messages boxes appear. One box says the following:

       RegClean.exe is linked to missing export OLEAUT32.DLL:421
    
    
    The next message box says the following:

       A device attached to the system is not correctly functioning
    
    

    Resolution

    You need to install the update to the OLE Automation system libraries. For additional information, please see the following articles in the Microsoft Knowledge Base:

       ARTICLE-ID: Q180071
       TITLE     : FILE: Msvbvm50.exe Installs Visual Basic 5.0 Run-Time Files
    
       ARTICLE-ID: Q192461
       TITLE     : FILE: VBRUN60.EXE Installs Visual Basic 6.0 Run-Time Files
    
    
    PROBLEM: IT DOESN'T SOLVE MY REGISTRY PROBLEMS OR IT JUST CREATES MORE PROBLEMS

    (status updated: December 30, 1997)

    Running RegClean may, in a few cases, cause other problems, such as causing part of the Microsoft Network viewer to stop functioning, or causing other programs to stop functioning. If this happens to you, simply Undo the changes RegClean made, by double-clicking on the last UNDO.REG file.

    These types of problems are very rare, but it's a good idea to keep your last UNDO.REG file for a few days or so.

    Microsoft will continue improving RegClean to reduce the frequency of problems like these.

    PROBLEM: CANNOT UNDO THE UNDO.REG FILE

    (status updated: March 18, 1997)

    Symptom

    Windows displays several error message boxes when you try to double-click the Undo.reg file to undo the changes RegClean made.

    Resolution

    This problem is unrelated to RegClean. It's a problem with the Associated Program for .reg files.

    Use the following steps to correct this problem:

    1. Go to any Explorer window, click the View menu, and select Options.

    2. In the Options dialog box, select the File Types tab.

    3. Scroll down in the "Registered file types:" list until you find the entry called "Registration Entries."

    4. Double-click this item or click on the Edit button.

    5. In the Edit File Type dialog box, select the "Merge" entry, and either double-click this item or click on the Edit button.

    6. In the "Editing action for type: Registration Entries" dialog box, make sure that the text in the "Application used to perform action:" field has the following entry, including the double quotes:

            regedit.exe "%1"
      

    7. Click the OK buttons to dismiss all three dialog boxes.

    8. You should be able to double-click on the Undo.reg file now.

    Thanks for using RegClean! We hope you find this utility useful.
    • The RegClean Team

    REGCLEAN IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.

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    Additional query words: registry clean update
    Keywords : APrgOther vb432 vb4all
    Technology : kbole
    Version : 4.1a build 7364.1
    Platform : NT WINDOWS
    Issue type : kbinfo


    THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.

    Last reviewed: October 5, 1998
    © 1998 Microsoft Corporation. All rights reserved. Terms of Use.