The Problem (Q-score 44, ranked #3rd of 95 in the VBA Core archive)
The scenario as originally posted in 2010
Now that Office also comes in a 64bit install, where in the registry do you find out if the version of Office installed is 32bit or 64bit?
Why community consensus is tight on this one
Across 95 VBA Core entries in the archive, the accepted answer here holds elite answer (top 10 %%) status — meaning voters are unusually aligned on the right fix.
The Verified Solution — elite answer (top 10 %%) (+45)
Advisory answer — community consensus with reference links
Note: the verified answer below is a reference / advisory response rather than a copy-ready snippet.
From TechNet article on 64-bit editions of Office 2010:
If you have installed Office 2010
including Microsoft Outlook 2010,
Outlook sets a registry key named
Bitness of type REG_SZ on the computer on which it is installed. The
Bitness registry key indicates whether the Outlook 2010 installation
is 32-bit or 64-bit. This may be
useful to administrators who are
interested in auditing computers to
determine the installed versions of
Office 2010 in their organization.
- Registry path: HKEY_LOCAL_MACHINESoftwareMicrosoftOffice14.0Outlook
- if you have installed Office 2013 then use this
Registry path: HKEY_LOCAL_MACHINESoftwareMicrosoftOffice15.0Outlook- Registry key: Bitness
- Value: either x86 or x64
and elsewhere in the same article:
Starting with Office 2010, Outlook is
available as a 32-bit application and
a 64-bit application. The version
(bitness) of Outlook that you choose
depends on the edition of the Windows
operating system (32-bit or 64-bit)
and the edition of Office 2010 (32- or
64-bit) that is installed on the
computer, if Office is already
installed on that computer.Factors that determine the feasibility
of installing a 32-bit or a 64-bit
version of Outlook include the
following:
- You can install 32-bit Office 2010 and 32-bit Microsoft Outlook 2010 on a supported 32-bit or 64-bit edition of the Windows operating system. You can install the 64-bit version of Office 2010 and 64-bit Outlook 2010 only on a supported 64-bit operating system.
- The default installation of Office 2010 on a 64-bit edition of the Windows operating system is 32-bit Office 2010.
- The bitness of an installed version of Outlook is always the same as the bitness of Office 2010, if Office is installed on the same computer. That is, a 32-bit version of Outlook 2010 cannot be installed on the same computer on which 64-bit versions of other Office 2010 applications are already installed, such as 64-bit Microsoft Word 2010 or 64-bit Microsoft Excel 2010. Similarly, a 64-bit version of Outlook 2010 cannot be installed on the same computer on which 32-bit versions of other Office applications are already installed.
When to Use It — vintage (14+ years old, pre-2013)
A top-10 VBA Core pattern — why it still holds up
Ranks #3rd of 95 in the VBA Core archive. The only pattern ranked immediately above it is “VBA – how to conditionally skip a for loop iteration” — compare both if you’re choosing between approaches.
What changed between 2010 and 2026
The answer is 16 years old. The VBA Core object model has been stable across Office 2013, 2016, 2019, 2021, 365, and 2024/2026 LTSC, so the pattern still compiles. Changes that might affect you: 64-bit API declarations (use PtrSafe), blocked macros in downloaded files (Mark-of-the-Web), and the shift toward Office Scripts for web-first workflows.