Address issue of ACEOLEDB.DLL in Office 2016 Pro Plus Install Affecting InfoPath 2013 Database Connectivity
After having worked with Microsoft Engineers for both the InfoPath 2013 & Access 2016 products, it was discovered that the ACEOLEDB.DLL file, as installed under C:\Program Files (x86)\Common Files\Microsoft Shared\OFFICE16 does not allow InfoPath 2013 to establish a data connection to Microsoft Access databases. The work-around solution is to replace ACEOLEDB.DLL with file of same name but from previous versions of Office before 2016 - ex. use the one from Office 2013 (which writes ACEOLEDB.DLL) into C:\Program Files (x86)\Common Files\Microsoft Shared\OFFICE15 instead.
Joe L commented
Addendum: If using above work-around, be aware that if one needs to import XML files, the non-Office 2016 version of the ACEOLEDB.DLL will NOT work. Access will fail in the process; solution is to restore original ACEOLEDB.DLL - but then you lose the ability to conduct InfoPath 2013 Access database links.
See this link as well for other users experiencing issue: https://answers.microsoft.com/en-us/msoffice/forum/msoffice_infop-mso_other/infopath-forms-connected-to-access-dont-work-in/a6061008-2765-4972-b3a9-f649a1176604