Most of the time, this error is related to the midas.dll.
What I usually do, uninstall Efficy product, unregister the midas.dll (from the command line as administrator : c:\Windows\System32>regsvr32.exe midas.dll -u
Then reboot yout computer.
After that, delete the existing midas .dll which is in c:\Windows\System32.
Reinstall Efficy. Don't forget to execute your setup with "right click run as administrator".
As kristof said, this it not related to the DB Engine.