The 64 bit version will require 64 bit ODBC-drivers. This is a particular problem with import from Microsoft Office programs as well as from text/CSV files when not using a DSN created explicitly but using the temporary file-DSN that SQLyog can create in the background. The problem is that 32 bit MS Office will install 32 bit drivers and after that 64 bit drivers cannot be installed (it is possible the other way around and 64 bit MS Office drivers are available for download. MS Office 2013 64 bit – and maybe also MS Office 2007 64 bit – installs 64 bit drivers that works fine with the 64 bit architecture of this release. Office 2010 did not have the option for 64 bit). This issue as well as non-availability of 64 bit drivers for some of your data sources may make you decide to stay with the 32 bit version or have both the 32 bit and the 64 bit version installed.”