Avoid pitfalls with Office 2010 64-bit Compatibilty

Office 2010 will be available in both a 32-bit and 64-bit version , so customers are asking “which version should my organization use?”Since many companies have more and more 64-bit systems deployed as they go through regular hardware upgrades, it would seem the logical choice would be to move to the 64-bit version of Office 2010. The obvious advantage is the extra memory available for those extremely large spreadsheets and databases used throughout the enterprise. Moving to 64-bit Office offers the chance to cut down on support calls generated because “my spreadsheet takes too long to open.”
However, there are  potential pitfalls that need to be considered before making the decision to move to 64-bit Office.  Here’s what we think are the most significant:

ActiveX Controls and COM Add-Ins

Documents that contain ActiveX controls are currently using 32-bit versions of these controls.These controls are not compatible with the 64-bit version of Office 2010. Make sure that there is a 64-bit version of all of the ActiveX controls your documents require to continue functioning.

VBA code

Declare statements for 64-bit Office 2010 are different than they are for 32-bit Office 2010. A new data type pointer is available, and required, for 64-bit Office. This may require some substantial work on your existing VBA code.


When considering Microsoft software compatibility issues, it is important to consider not only the author of a document but the audience as well. If one department is creating documents using 64-bit Office, can you be sure that everyone in the company who will be reading or updating these documents are also  on 64-bit Office 2010? Even more challenging is knowing whether or not anyone outside of your organization who may be collaborating on your documents will be using the 32 or 64 bit version of Office 2010.
Although taking advantage of the latest and greatest technology is very appealing and often advantageous to an organization, the 32-bit version of Office 2010 is generally the wise choice for now. Until vendors have recompiled applications that interact with Office as 64-bit applications, until all of the desired ActiveX controls and COM AddIns are updated and until more customers and vendors are ready and able to move to the 64-bit version of Office 2010, the compatibility challenges will continue to be greater than the benefits of 64-bit Office (see the Microsoft Office 2010 Engineering blog for Microsoft’s recommendation).
What version of Office 2010 will your organization be deploying?