Problem scenario
In Windows 7 you start (or launch) HeidiSQL. You try to connect to a remote server but you get the error "Cannot find a usable libpq.dll. Please launch heidisql64.r5168.exe from the directory where you have installed it." How do you solve this problem?
Solution
Uninstall HeidiSQL and install the latest one from here. If you download the latest build, the problem may remain. You may need the installer.