On Windows XP, "Unable to launch or to connect to the Diskeeper service. Possible causes are that another Diskeeper process is currently connected to this computer or Diskeeper is not installed correctly".

Some errors may occur because your computer has insufficient Component Object Model (COM) access permissions or the COM Default Impersonation Level is set improperly. COM is a Microsoft-developed software architecture that allows for the creation of component-based applications. Component-based applications allow other components and other applications to use their features. For example, COM allows you to embed a Microsoft Excel chart into a Microsoft Word document. The most common errors received related to COM are "Setup failed to launch installation engine: Access is denied." and "Error installing Ikernel.exe, access is denied."
Procedure
The following procedure modifies the COM access permission settings on your computer.
1. Select Start > Run.
2. Type dcomcnfg. Click No for any warning screens that appear. This launches the Component Services dialog.
3. Double-click Component Services.
4. Double-click Computers. My Computer will be listed in the right pane.
5. Right-click My Computer and select Properties. The My Computer Properties dialog opens.
6. Select the Default COM Security tab.
7. In the Access Permissions section, click Edit Default. The Access dialog opens.
8. Make sure you, as the user, or System is listed and the Access Permission check box is selected.
9. If you or System do not have Allow Access next to your name, select the Access Permission check box. Or create a new profile wit the necessary permissions.
a. Click Add. The Select Users or Groups dialog opens.
b. In the Select this object type field, make sure that at least Users is entered. If not, click Object Types and select Users.
c. In the From this location field, make sure your computer name is entered. If it is not, click Locations and select your computer.
d. In the Enter objects name to select field, type a new object. Click OK.
e. In the Access dialog, select the new object.
f. Select the Allow Access check box.
g. Click OK twice.
10. Close the Component Services dialog.
11. Run your installation again.
The following procedure sets the Default Impersonation Level to Identify.
1. Select Start > Run.
2. Type dcomcnfg. Click No for any warning screens that appear. This launches the Component Services dialog (pictured above).
3. Double-click Component Services.
4. Double-click Computers. My Computer will be listed in the right pane.
5. Right-click My Computer and select Properties. The My Computer Properties dialog opens.
6. Select the Default Properties tab (see the figure directly above).
7. The Default Impersonation Level field must be set to Identify.
8. Select Apply and click OK.