RegClean 4.1a Description and General Issues

Q147769

The information in this article applies to:

WORKAROUND

For Windows ME, Windows 2000: To resolve this issue:

  1. Open any Windows Explorer window, and then click Folder Options on the Tools menu.


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


  3. Scroll down in the "Registered file types" list until you find Registration Entries. The list is sorted alphabetically by extension. Left click on the "File Types" tool bar to resort by file types.


  4. Click Registration Entries, and then click Advanced.


  5. In the Edit File Type dialog box, click Merge, and then click Edit.


  6. In the Editing action for type: Registration Entries dialog box, make sure that the "Application used to perform action" box contains the following text, including the quotation marks: regedit.exe "%1"


  7. Click OK to close all of the dialog boxes.


  8. If Merge is not listed, select "New". In the New Action dialog box enter "Merge" in the "Action" field and "regedit.exe "%1"" in the "Application Used to Perform the Action"


  9. Click OK to close all of the dialog boxes.


NOTE: if Merge is not listed, then it is possible that it was removed by an administrator to prevent the spread of viruses. Care should be taken whenever importing contents into the registry. An alternative is to use Regedit to manual import the file. In REGEDIT.EXE, select "Import registry file" from the Registry menu. In the file dialog box select the Undo file created by Regclean and click on Open.


MORE INFORMATION

When you install, uninstall, or reinstall programs on your computer, registry keys are created, modified, or deleted. Over time, a computer's registry may accumulate corrupted, unused, or unnecessary registry keys, especially if registry keys are not removed when you uninstall a program. Therefore, you may experience issues when you use OLE to embed objects, or when you use automation to control other programs. The RegClean utility cleans up these unnecessary registry entries in the registry.

The RegClean utility was originally included with Microsoft Visual Basic for Windows, version 4.0. The RegClean utility was updated in the Microsoft Office 97 Resource Kit to version 4.1a. RegClean 4.1a is the latest version.

What RegClean Does

RegClean analyzes Windows registry keys that are stored in the HKEY_CLASSES_ROOT key in the registry and finds keys that contain erroneous values. RegClean records those entries in an Undo.reg file that has the following file name (where computer is the name of the computer, yyyymmdd is the date, and hhmmss is the time):
Undo computer yyyymmddhhmmss.reg
RegClean then removes the erroneous entries from the registry.

What RegClean Does Not Do

RegClean does not fix every known issue with the registry. RegClean does not fix a corrupted registry; RegClean fixes issues in standard registry entries that are located in the HKEY_CLASSES_ROOT key.

RegClean might not correct an issue that you have encountered. RegClean leaves intact any registry entries that RegClean does not understand or that might be correct.

How to Install RegClean

Copy the RegClean.exe file (version 4.1a, build 7364.1) to any folder on your computer.

The following file is available for download from the Microsoft Download Center:
[GRAPHIC: Download]Download RegClean.exe now
For additional information about how to download Microsoft Support files, click the article number below to view the article in the Microsoft Knowledge Base:
Q119591 How to Obtain Microsoft Support Files from Online Services
Microsoft used the most current virus detection software available on the date of posting to scan this file for viruses. Once posted, the file is housed on secure servers that prevent any unauthorized changes to the file.

How to Run RegClean

  1. Double-click the RegClean file in the folder in which you copied it. RegClean displays a progress dialog box. While the progress dialog box is displayed, RegClean loads a copy of the parts of the registry that RegClean scans, and then performs the actual scanning. Depending on the amount of information in the registry and the speed of your CPU, this scanning may take from 30 seconds to 30 minutes.

    If the registry contains many entries, RegClean might seem to stop working. RegClean also might seem to stop working whenever RegClean checks remote or removable drives. However, RegClean is still working.


  2. After the progress meters have disappeared, you are prompted to select the next action. You can choose one of the two following options:


RegClean Issues

RegClean Requires the Updated Oleaut32.dll File

Symptoms:

The following error message may be displayed:
RegClean.exe is linked to missing export OLEAUT32.DLL:421
Then the following error message is displayed:
A device attached to the system is not correctly functioning
Cause:

This issue occurs with an earlier version of RegClean. For RegClean to work on a computer, the computer must have the updated version of the Oleaut32.dll file.

Resolution:

To resolve this issue, make sure that the computer has the updated version of the Oleaut32.dll file.

If the computer is running Microsoft Internet Explorer version 2.0 or earlier, you can update the Oleaut32.dll file by installing Internet Explorer version 3.0 or later. If the computer is running Windows NT 3.51 Service Pack 4 or earlier, you can update the Oleaut32.dll file by installing Windows NT 3.51 Service Pack 5.

The updated Oleaut32.dll file is also part of the Msvbvm50.exe and Vbrun60.exe files that are available from the Microsoft Download Center. For additional information about downloading the Msvbvm50.exe and Vbrun60.exe files, click the article numbers below to view the articles in the Microsoft Knowledge Base:
Q180071 FILE: Msvbvm50.exe Installs Visual Basic 5.0 Run-Time Files
Q192461 FILE: VBRun60.exe Installs Visual Basic 6.0 Run-Time Files

RegClean Does Not Resolve Registry Issues, or RegClean Creates More Issues

Symptoms:

RegClean may cause other issues (for example, part of the Microsoft Network viewer may stop functioning, or other programs may stop functioning).

Resolution:

To work around this issue, undo the changes that RegClean made by double-clicking the latest Undo.reg file. This issue occurs very rarely, but it is still a good idea to keep the latest Undo.reg file for at least few days.

Cannot Undo RegClean Changes by Using the Undo.reg File

Symptoms:

Windows may display several error messages when you try to double-click the Undo.reg file to undo the RegClean changes.

Cause:

This issue is unrelated to RegClean. This issue occurs because of a behavior with the associated program for .reg files.

Resolution:

To resolve this issue:
  1. Open any Windows Explorer window, and then click Options on the View menu.


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


  3. Scroll down in the Registered file types list until you find Registration Entries.


  4. Click Registration Entries, and then click Edit.


  5. In the Edit File Type dialog box, click Merge, and then click Edit.


  6. In the Editing action for type: Registration Entries dialog box, make sure that the Application used to perform action box contains the following text, including the quotation marks:


    7. regedit.exe "%1"
  7. Click OK to close all of the dialog boxes.


After you perform these steps, you should be able to double-click on the Undo.reg file to undo the RegClean changes.

NOTE: RegClean is not supported, nor been tested on Windows Millennium Edition (Windows Me). To remove invalid entries and empty data blocks in Windows Me, use the ScanReg tool. For additional information about the ScanReg tool, click the article number below to view the article in the Microsoft Knowledge Base:
Q183887 Description of the Windows Registry Checker Tool

Additional query words: registry clean update

Keywords : kbVBp kbVBp400 kbVC kbvfp500 kb32bitOnly kbVBP500FAQ
Issue type : kbhowto
Technology : kbWinNTsearch kbWinNTWsearch kbWinNTSsearch


Last Reviewed: March 15, 2001
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