Installing SQL Server 2000 can cause a serious problem

Phenomenon

My machine calls Microsoft's CDO or CDOEX access to Exchange mailboxes has an exception! And ADSI is not working properly. From the outside, there is no sign of error.

The following steps are reproduced:

Create an application in VB;

Quoting CDOEX.DLL;

Code writes:

Set oMsg = CreateObject("CDO.Message")　
oMsg.DataSource.Open(“http://BackEndServer/public”)

You get the same error in the second line:

Run-time error '-2147221164 (80040154) ':

Unable to write entry to registry

Frontendserver configuration:

Windows Advanced Server 2000 build number 2195:service Pack 2

IE Version: 5.00.3315.1000 Updated version: SP2

CDOEX. Version number of DLL: 6.0.4417.0

Where it is located: C:\Program files\common Files\Microsoft

Reason

First, before frontendserver installs SQL Server 2000, we can open the user's mailbox by using CDOEX's Idatasource.open:

_ConnectionPtr pCon = NULL;
CComPtr <CDO::IFolder>pFldr;
CComPtr <CDO::IDataSource>pSource;
hr=pFldr.CoCreateInstance(L"CDO.Folder");
pFldr->get_DataSource(&pSource);
hr=pSource->Open(bstrURLInbox,
(IDispatch*)pCon,
adModeRead,
adFailIfNotExists,
adOpenSource,
bstrUserDomainAccount,
bstrUserPwd);

However, after installing SQL Server, MDAC is updated to version 2.6!!

As a result of Microsoft's fault, some of the early MDAC components were deleted or overwritten by MDAC 2.6!!

Running Idatasource.open, which is required to reference these deleted components of MDAC 2.5, will report a "Class not registered" error.

At this point, if you run the following code:

Set con = CreateObject("ADODB.Connection")
　　con.Provider = "ADsDSOObject"
　　con.Open "ADs Provider"

The last row failed with an error:

run-tim error 429 ''''ActiveX component
can''''t create object''''

This situation is called by the newsgroup people:

“ADSI toasting ADO”!!

This is a very serious problem. Your program to use the interface to the previous ADO may not work!

So, after installing SQL Server 2000, be sure to download the latest MDAC installation pack or patch.

The solution to this CDOEX problem is to download and install the MDAC 2.6 SP1 (2.61.7326.6). exe.

Summary

Be aware of this issue when installing SQL Server 2000 on any machine!

Once you have discovered that a program that can run is now out of some inexplicable error, update the MDAC on this machine or play SQL Server SP1 first.