cacti error after install "Manage" plugin

[areast]

HI All

Have experience on plugin install with fresh cacti 0.8.8h on window server
Everything thing work fine until install "Manage" then cacti was down straight away

Configuration -> Plugin Management -> Manage (0.6.2)
Pres the install arrow then browser turn into "http://localhost/cacti/plugins.php" Error 500

Other plugin was found just "Manage" have this happen

[Osiris]

Don't know if anyone is supporting that plugin any longer.