Event id 1542, User Profile Service and Missing Classes Root Key


  • How may I fix this error in Windows 7? I get Class not registered

    Log Name:      Application
    Source:        Microsoft-Windows-User Profiles Service
    Date:          5/17/2010 10:27:05 PM
    Event ID:      1542
    Task Category: None
    Level:         Error
    User:          SYSTEM
    Computer:      DonB-PC
    Windows cannot load classes registry file.
     DETAIL - The system cannot find the file specified.

    Event Xml:
    <Event xmlns="">
        <Provider Name="Microsoft-Windows-User Profiles Service" Guid="{89B1E9F0-5AFF-44A6-9B44-0A07A7CE5845}" />
        <TimeCreated SystemTime="2010-05-18T03:27:05.617582400Z" />
        <Correlation />
        <Execution ProcessID="1076" ThreadID="4012" />
        <Security UserID="S-1-5-18" />
        <Data Name="Error">The system cannot find the file specified.

    Regards, Donald
    Tuesday, May 18, 2010 3:27 AM

All replies

  • Hi,


    Based on my research, this issue can potentially be caused by the following:


    1)    The profile is corrupted.

    2)    The  UsrClass.dat file at the following location is missing: %userprofile%\AppData\Local\Microsoft\Windows.

    3)    Folder redirection is enabled to redirect Application Data folder into a Roaming Profile.


    To resolve this issue, I would like to suggest:


    1)    Locate the folder: %userprofile%\AppData\Local\Microsoft\Windows, verify if UsrClass.dat is present.

    2)    Create a new user profile and fix the corrupted user profile.



    BTW, if the issue persists, try the following work around:

    1)    Disable the "User Profile Service".

    2)    Reboot.

    3)    Log on with local admin account.

    4)    Remove the problematic profiles.

    5)    Remove reference to the specific problematic profiles from registry at:


    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileListLogoff


    6)    Log on with local admin account.

    7)    Set "User profile Service" to start automatically.

    8)    Reboot.


    Best Regards



    • Marked as answer by Dale QiaoModerator Monday, May 24, 2010 1:51 AM
    • Unmarked as answer by DonaldBCrip Saturday, May 29, 2010 3:23 AM
    • Proposed as answer by Michi Fees Wednesday, October 1, 2014 3:27 PM
    Tuesday, May 18, 2010 7:13 AM
  • For solving the above problem we used the third party utility Reprofier.

    Download link:

    Login with default login user account. Open the Reprofiler utility. Select the corrupted user profile and select assign as shown in figure.



    And restart the machine


    Regards Jinish.K.G
    Monday, October 24, 2011 6:05 PM