Microsoft Office 2010 is found to be compatible with Windows 7, Windows Vista SP1, and Windows XP SP3 on both 32-bit Office 2010 and 64-bit Microsoft Office 2010. Except for Windows Server 2003 R2 with MSXML 6.0, which is only compatible with 32-bit Office 2010, you might be able to install to all other Operating System. But due to any reason if these files get corrupted or some files get deleted, then you might not be able to install Microsoft Office 2010 on Windows Vista system.