The 64 bit version of our software is faster, can open lager images and larger database files than what is possible with 32 bit. This makes 64 bit the advised version of our software, however due to limitations described below this is not always possible. Our applications use a Microsoft module that is also used by Microsoft Office, and Microsoft does not allow a mix of 64 bit and 32 bit on the same pc. This means that the module installed must match any previous 32/64 bit module installed and if applicable it must also match the 32/64 bit version of Microsoft Office
As said above, we advice 64-bit, not only is it faster and can handle larger files, but new pc's will be 64-bit by default and will have, more often than not, a 64-bit (trial) office version installed.

• If Microsoft office is installed, it is required to be the 64-bit version.
  Microsoft Office 2010 or later can be installed as 64-bit with the same license.
• No 32-bit version of FlexMail and FlexStream can be present on the pc.

This is the option you choose if you need to run both versions of FlexMail (4.0 & 4.2) or both versions of FlexStream (1.0 & 1.2) on a single pc.

• If Microsoft office is installed, it is recommended to be the 32-bit version.
• No 64-bit version of FlexMail and FlexStream can be present on the pc.

If you keep getting errors, manualy uninstall Microsoft Access Database Engine 2010 with 'Program and features' in the windows controll pannel. There might be two entries, uninstall them both. Then install the correct version, either 64-bit or 32-bit. Downloads for manual installation.
note: it is possible to install 32-bit version next to a 64-bit office installation. Be sure to start the AccessDatabaseEngine.exe with the /passive paramter. This can be done with cmd.exe, execute "AccessDatabaseEngine.exe /passive" from the download location.