Just as has been the case in previous Release To Market products, Office 2010 will require that the Release Candidate or Beta versions of the product be uninstalled prior to running the install:
Setup is unable to proceed due to the following error(s):
Microsoft Office 2010 does not support upgrading from a prerelease version of Microsoft Office 2010. You must first uninstall any prerelease versions of Microsoft Office 2010 products and associated technologies.
Correct the issue(s) listed above and re-run setup.
Fortunately we do not have a lot of workstations with the Release Candidate installed so the time required to “correct the issues” will not be too consuming.
One more thing to keep in mind too:
If there is a plan to use the 64bit version of Office 2010, then any installed 32bit of Office will need to be removed prior to the install too.
Microsoft Small Business Specialists
Co-Author: SBS 2008 Blueprint Book