To determine the bit architecture of the installation of MS Office on a Windows PC, do the following.

Using Office 2010:

1. Start Excel.
2. Within a blank worksheet, select File ► Help to display the About Microsoft Excel information. This information includes the product version and bits. Here is an example:
   Version: 14.0.6023.100 (32-bit)

Using Office 2013:

1. Start Excel.
2. Within a blank worksheet, select File ► Account to display the About Microsoft Excel information. This information includes the product version and bits. Here is an example:
   Microsoft Excel 2013 (15.0.4454.1503)....32-bit

Operating System and Release Information