Microsoft ADO Bug

Fixing MDAC/ADO Corruption in XP
MDAC 2.8 RTM is incompatible with this version of Windows

Repair Method A (medium difficulty)

Customers have reported this "short cut" to re-installing has worked for them. Basically what this does is reinstall MDAC/ADO from your Windows CD.

A) Right click on the file c:\windows\inf\mdac.inf, then select install.

B) When prompted for a location, Choose c:\windows\servicepackfiles\i386 then XP will ask for the cd for XP, Use the original CD or the location c:\i386. This will re-install the MDAC that came with Windows XP, SP2.

C) After you perform STEP 1 from the above link, return to where where you left off at http://www.GenSmarts.com/msWin.html

NOTE) The "inf" folder is probably a "hidden" folder so you'll have to TOOLS...FOLDER OPTIONS... to display hidden folders and files.

Repair Method A2 (medium difficulty)

If you don't have a file/folder on your PC called c:\windows\servicepackfiles\i386, it may be that you didn't "upgrade" to SP2, but rather have a PC that had it installed initially. So that/folder those files you need are on the XP CD. In that case:

As before in Method A), go to and find c:\windows\inf\mdac.inf. Right click on the .inf file and pick Install. It will attempt to reinstall the files. Now, don't specify a "C:\" source on your hard drive, but rather browse to source files on your XP Installation CD. It should install smoothly. It may ask for the handler.reg (which you'll find in c:\program files\common files\system\msadc). You'll likely have to restart your PC after this completes.

Repair Method B (medium difficulty)

Go to Microsoft's own solution for this error:
http://support.microsoft.com/kb/899861

In theory, you'd think that you could simply follow Microsoft's instructions, but it appears this too often requires secret work arounds.

Use their "Method 1" to install MDAC 2.81. Keep track of where the MDAC_TYP.EXE file goes on your PC as you download it.

If you get the error "this setup does not support installing on this operating system", right click on the MDACTYP.EXE file and select properties, then the compatibility tab. Click on the "Run this program..." box, and select Windows NT from the drop down list. Then click OK. Now double click on the MDACTYP.EXE file to run it again - you should no longer get the "does not support" message.

Repair Method C (easy, but time consuming)

Assuming you manually applied SP2 to your XP at some point.... just uninstall SP2 (you can use the control panel), then you'll be able reinstall MDAC (as per http://www.GenSmarts.com/msWin.html ), and then you can re-apply the SP2 patch.

A) Using Windows Control Panel, uninstall the MS SP2 patch.

B) Return to where you were in the instructions at http://www.GenSmarts.com/msWin.html ... try the re-install of MDAC/ADO again - you won't get the "RTM" error any more.

C) After you have GenSmarts working, redownload/reapply the MS SP2 patch.

Other Repair Methods

There are likely other ways of fixing this... the above are simply the approaches that other customers have told us about (e.g. they work). Google the error message you are receiving if you want some additional alternatives.