SQL Server/ADO/XP Problem Query Cannot Be Executed

This is a request for help fixing a SQL Server 2000/ADO problem on Windows
XP. I would appreciate any useful assistance.

PROBLEM: SQL Server access on my machine fails as follows:

1. All of my VB6 apps reference the following ADO typelib:
Microsoft ActiveX Data Objects 2.7 Library

Located at:
c:Program FilesCommon FilesSystemADOmsado27.tlb

When I open one of these projects in VB6, the reference to msado27.tlb is
shown as MISSING. If I remove the reference then open the references dialog
again, msado27.tlb is listed normally. When I check it and try to close the
references dialog, I take an "Error in loading DLL".

I can remove the reference to msado27.tlb and add a reference to msado15.dll
(Microsoft ActiveX Data Objects 2.8 Library).

When I run the app, I take a trappable error on the first ADO line my app
executes:

Dim lo_Connection As ADODB.Connection

Set lo_Connection = New ADODB.Connection

The error is:
Automation error
The specified procedure could not be found.

2. In Enterprise Manager, when I do "Open Table/Return All Rows" on any
table, I take the following error:
"The query cannot be executed because some files are either missing or not
registered. Run setup again to make sure the required files are
registered."


CURRENT CONFIGURATION
I develop software in VB6 that accesses SQL Server via a dsn-less
connections and disconnected recordsets. I am running SQL Server 2000
Standard locally, version installed from the MSDN install CD and updated by
service pack download.

SQL Server version: version 8.00.760 (SP3)

VB version: VB6 SP5

Component Checker 2.0 shows no problems, and reports:
The following product releases were matched: MDAC 2.8 RTM.

My OS is Windows XP Home. As far as I can tell, it is completely updated
with all hotfixes, including the following:
KB810218
KB820291
KB821253
KB822603
KB823182
KB824105
KB824141
KB826939
KB828035
KB829558
Q322011
Q327979
Q814995
Q815485


ATTEMPTS TO FIX
A. I have uninstalled and reinstalled SQL Server and client tools *numerous*
times with no change.

B. Queries in Query Analyzer execute just fine.

C. The last four lines out of sqlstp.log (located in c:Windows) are as
follows:

12:40:04 StatsGenerate returned: 2
12:40:04 StatsGenerate (0x0,0x1,0xf000000,0x100,1033,303,0x0,0x1,0,0,0
12:40:04 StatsGenerate -1,George Copeland)
12:40:04 Installation Succeeded

D. The only services running during setup are those specified by Microsoft
KB article 192710. There are no relevant errors in the event log.

E. I tried reinstalling MDAC 2.7 SP1 Refresh and MDAC 2.8. No change.

F. Microsoft KB Article 315868
(http://support.microsoft.com/defaul...Ben-us%3B315868) says
the following:

If the reinstallation of the SQL Server 2000 Client Tools does not correct
the problem, then re-register the following DLLs by using Regsvr32.exe, and
then restart the computer:
C:Program filesCommon FilesSystemADOMsado15.dll
C:Program filesCommon FilesSystemOle DbOledb32.dll
C:Program filesCommon FilesSystemOle DbSqloledb.dll
C:WINNTSystem32Atl.dll

Attempting to register the first three dlls fails with
"LoadLibrary("C:Program filesCommon FilesSystemADOMsado15.dll")
failed - The specified procedure could not be found.". In any case, this
does nothing to fix the problem. And since these link libraries are not
registerable, this KB article is just a little, shall I say, unhelpful.


Please note that the MS newsgroups are FULL of requests for help on this
EXACT problem. All attempts to help have failed--NOBODY has figured out the
fix. Most people trying to help are treating it as an installation issue,
because that is what the error message says. However, I suspect instead
that a Windows XP hotfix has CLOBBERED ADO.

BTW, this is a BIG issue for me. My development machine is hosed, and until
I get this fixed, I AM COMPLETELY DOWN.