- Sites showing 'The FastCGI executable could not be found' error when php handler changed to newer php version.
- Plesk was not completely upgraded The FastCGI executable could not be found
Required PHP binary is missing.
Install older PHP version once again "C:\ParallelsInstaller\parallels\PANEL-WIN_12.0.18\dist-msi-Microsoft-2003-i386\plesk-engine.msi"
Move all your websites on newer php version
Later, If you want you can remove older PHP versions