I'm running VB 6.0 on a Win 98 computer. I've been having a little trouble here and there, and thought that I'd better reinstall VB.
When I try to reinstall, it bombs saying:
VB was unable to register DAO350.dll in the registry. VB did not complete sucessfully.
After trying everything I could think of, I backed up my registry, and deleted every instance of DAO350.DLL, and rebooted. When I reboot, Windows itself replaces DAO350 into the registry.
Has anyone had a similar problem, and what to do?
05-10-2002, 01:19 AM
Reinstall the Microsoft database drivers.
You can find here: www.microsoft.com/data
Be sure you take version 2.5, because the higher versions don't include DAO anymore.
I downloaded MDAC 2.5 SP 2 and installed it. Then rebooted, and tried again.
Got the same error (which says EXACTLY..."dao350.dll was unable to register itself in the system registry."
When I got VB 6 SP 5, I vaguely remember having to update to MDAC 2.7 before loading the service pack. Does just running MDAC 2.5 overwrite what it needs to??
05-10-2002, 12:21 PM
Once you have installed 2.7, you can't go back and put on 2.5.
Look for Jet40sp3_comp.exe at
If you are sure you have installed 2.6 or 2.7 of mdac_typ.exe,
then this is what you need to install.
I downloaded Jet40SP3_comp.exe and ran it, Rebooted, Reran VB Setup, and still got the same result.
05-10-2002, 03:20 PM
Ok, how far into the install do you get before this error comes up?
I assume it doesn't get far enough for you do try to start VB IDE?
It finishes copying the files, and it's saying "Updating System Files" when it errors.
05-10-2002, 05:04 PM
Do a search of your system for DAO350.DLL. It should be in
somedisk:\Program Files\Common Files\Microsoft Shared\DAO.
If you find it, open a Dosbox command prompt, move to that
directory, and type in Regsvr32.exe dao350.dll. Post back what
Also, while you are looking at that directory, see if you also have
I've been there already. I DO have it in
C:\\Program Files\Common Files\Microsoft Shared\DAO.
I am a little confused about whether it SHOULD be there or should be REMOVED (since it appears that VB is trying to re-register it).
I did manually re-register it already, as you suggest, and the re-register happened perfectly & quietly with no problem. Same error occurs when I try to reinstall VB, though.
BTW, I have DAO350.DLL 5 or 6 places in my system. (I also have DAO360.dll in the directory listed above.)
Well, I'm not at work any longer, so troublshooting will take a break until Monday, however, I did find a posting on the web that may be the answer... I didn't mention that my computer is on a network, because I didn't realize that that might be significant. The attached isn't EXACTLY the error message that I'm getting, but may be due to the same cause.
I will try the recommended solutions when I get back.
I'll post a result. Please see the attached.
Can't attach a PDF... so here tiz...
DOCUMENT:Q182150 11-JAN-2001 [vbwin]
TITLE :PRB: Visual Basic 5.0 Setup Error: DAO350.DLL File In Use
PRODUCT :Microsoft Visual Basic for Windows
The information in this article applies to:
- Microsoft Visual Basic Learning Edition for Windows, version 5.0
- Microsoft Visual Basic Professional Edition for Windows, version 5.0
- Microsoft Visual Basic Enterprise Edition for Windows, version 5.0
Setup of Visual Basic 5.0 fails with the following error:
Setup cannot register DAO350.DLL because an older version is in use.
The computer has a network installation of Office 97 with the shared files
(including DAO350.DLL) on the network server in a read-only folder.
IMPORTANT: This article contains information about editing the registry. Before
you edit the registry, make sure you understand how to restore it if a problem
occurs. For information about how to do this, view the "Restoring the Registry"
Help topic in Regedit.exe or the "Restoring a Registry Key" Help topic in
There are two primary solutions to this error:
1. Search the registry for the following key, and export a copy of it for
safekeeping. Delete the key from the registry, then run the Visual Basic 5.0
setup. After the setup is finished, import the saved registry key to ensure
that the Office applications are not affected.
2. Perform the Visual Basic 5.0 installation only when all users are off the
server and with update permissions on the server. Network administrative
policies may not allow this option.
Microsoft is researching this problem and will post new information here in the
Microsoft Knowledge Base as it becomes available.
The Visual Basic 5.0 setup process checks the registry for existing entries to
DAO files and attempts to update them. If located on the local drive, DAO files
would be placed in following location:
Program Files\Common Files\Microsoft Shared\DAO\
If Office is installed with shared files residing on the network, the folder with
DAO350.DLL file is read-only, and the user may not have permissions to write to
that server directory. In this case, updates cannot not be made and the setup
Microsoft Office97 installs DAO350.dll v3.50.3428 dated 11/17/96. Microsoft
Visual Basic 5.0 installs v3.50.3602 dated 12/5/96.
The registry key for the shared location of DAO 3.5 files is:
Additional query words: kbVB500 kbNetwork kbSetup kbDAO kbDSupport kbdss
Keywords : kberrmsg kbGrpDSVB
Technology : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVBA500 kbVB500
Version : WINDOWS:5.0
Issue type : kbprb
THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS
PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS
ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO
EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR
ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL,
CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF
MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION
OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES
SO THE FOREGOING LIMITATION MAY NOT APPLY.
Copyright Microsoft Corporation 2001.
05-11-2002, 10:45 AM
That looks like a very good possibility. I was going to suggest
next that you unregister the dao350.dll and then rename it to
something else and see if the VB install worked, but their idea
sounds better. You should check to see if that file or folder is
On my win98 with Office 97 and VB6 enterprise and mdac_typ 2.5,
my dao350.dll is version 3.51.1608.0 04/27/1998
In my registry, I have both
They both have clients and no client is duplicated.
The above proceedure DID NOT work.
I removed the key mentioned.
I did NOT log onto the network.
I removed all instances of DAO350.DLL (after backing up registry)
Attempted a re-install.
Got the same error as before.
Hmmm. Seems like a good day to reformat ;-)
05-13-2002, 04:24 PM
Just curious. Since you deleted all instances of DAO350.dll, did
you look to see if the install process put one back on your system?
Did you by any chance unregister the DAO350.dll before deleting