Fatal error: Incompatible file format

[theMezz]

( I HAVE TESTER INSTALLED http://midstateems.org/tester/ )

Tryng to install newest version and get this...

Fatal error: Incompatible file format: The encoded file has format major ID 2, whereas the Optimizer expects 1; The encoded file was probably encoded by the Zend Guard for PHP 5 (zendenc5), and therefore cannot be run on PHP 4 in /home/.harimau/uticafor/midstateems.org/calendar/calendar/setup/index.php on line 0

any ideas?

[ve9gra]

Exactly what it says... You tried to install the Zend version for PHP5 while your server is running PHP4 (4.4.7 according to Tester). Download the appropriate version from the Tester screen.