I have been puzzled with this problem for months and unable to resolve it until today.

When you have two version of Microsoft Office which Access is part of the suite, let say Office 97, 2000 or Office XP or 2003 and when a normal user is trying to open their Microsoft Access database MDB file by double click on the file but it will fail with a message "...fail to initialize Windows registry..."

The trouble comes in is when you have 2 versions of Microsoft Access running on the same user workstation every time you double click on the MDB file or the shortcut to any version of Microsoft Access, it will try to do a registry repair and register its version of run time. This run time register process does not always work for the normal user and they will get a failure message to open the MDB file. The message would be something like "...unable to initialize Windows Registry, please re-install Access...". This problem happens on Window XP professional.

The trouble with re-install Access are it will take time and sometimes it does not fix the problem.

I have been searching the Google, Microsoft website, user community forum and everywhere for the fix but come up empty. It finally dawns on me that this problem might be related to the conflict with the different version of Access run time. Somewhere in my head, I remember reading a knowledge base article at Microsoft website on how to manually register a particular Access runtime on your computer.

So I thought I might give it a try! Heck, I have nothing to loose after all this time trying.

So I go to a computer that is having this problem and go to the directory of the latest version of Microsoft Access and run this command: “msaccess.exe /regserver" without the quote. What this command does is to set up the proper Microsoft Access runtime environment for that particular version of Access.

Warning: Please be aware that registry hacking is a sensitive operation.
Sometimes you have to do this to fix the registry and assuming you are using version 8. Please make sure to replace %machine% with your machine name.
SetACL.exe \\%machine%\MACHINE\Software\Microsoft\Office\8.0 /registry /grant users /read
SetACL.exe \\%machine%\MACHINE\Software\Microsoft\Office\8.0 /registry /grant users /query_val
SetACL.exe \\%machine%\MACHINE\Software\Microsoft\Office\8.0 /registry /grant users /set_val
SetACL.exe \\%machine%\MACHINE\Software\Microsoft\Office\8.0 /registry /grant users /create_subkey
SetACL.exe \\%machine%\MACHINE\Software\Microsoft\Office\8.0 /registry /grant users /enum_subkeys
SetACL.exe \\%machine%\MACHINE\Software\Microsoft\Office\8.0 /registry /grant users /notify
SetACL.exe \\%machine%\MACHINE\Software\Microsoft\Office\8.0 /registry /grant users /delete

After I did this my user was able to switch between versions of Access without further problem.

I have so happy I finally found the solution to this problem and publish this article.

Hopefully, you will find this useful!