Andrew's Guide to Computers

Problem

Explorer.EXE - Application Error

The application failed to initialize properly (0xc0150002). Click on ok to terminate the application.

This error can occur if the computer does not complete applying Microsoft Windows Update KB923191, which attempts to fix a security hole relating to ActiveX implementation. The following symptoms occur:

The computer boots successfully to the login prompt.
However, only the traditional NT style login prompt is displayed, not the welcome screen.
On successfully logging in, the user is greeted with the above error.
On clicking OK, the user is left with a completely blank desktop. Crtl + Alt + Del does not work.
Neither uninstalling or applying the patch in full appear to resolve the problem.
Microsoft offer no fix to the problem beyond the usual "reinstall".

The following steps taken were unsuccessful:

Running a repair reinstall of Windows XP Home SP2.
Running chkdsk
Booting the computer into Safe Mode, Safe Mode with Networking Support, or Last Known Good Configuration.
Uninstalling the patch via spuninst.exe contained within the C:\Windows\$NtUninstallKB923191$ directory structure.

Solution

This problem was repaired by replacing the following two folders from the same folders on another working Windows XP SP2 install (or a parallel install) without the patch having been applied:

%windir%\WinSxS
%windir%\SoftwareDistribution

Read/write access must be gained to the drive, which can be done through Microsoft's recovery console, BartPE, or another method.

The failure is almost certainly due to just one file in one of these directories, but as of 22/10/2006, I am unable to be any more specific.

Partial Solution

Before the problem was solved, we managed to make a command prompt window appear after login by booting the system off a BartPE disc and altering the HKLM \ Software \ Microsoft \ Windows NT \ CurrentVersion \ Winlogon \ Shell DWORD to point to %windir/system32/cmd.exe.

Notes

Other victims might have luck either reinstalling the KB923191 update from Microsoft (if they are able to download and run it), or by uninstalling the update via it's spuninst.exe contained within the hidden C:\Windows\$NtUninstallKB923191$ directory structure. This didn't work in this case however.