I have had this problem for a while now and can't find the problem at all. When i open a page it will sometimes give a 500 Internal Server Error message.

This hapens on a website that works perfectly but when i try to upload anything it will give this message(all php settings have been set to either 1gb or 3000 seconds as well as the iis headers).

Also when i open a simple page which does nothing more than include another php page and include a couple of classes the error will occur.

I have no idea what causes this error and would love to hear from any of you on what this could be. I checked the server logs and for the upload issue i found this error:

The description for Event ID 1 from source named cannot be found. Either the component that raises this event is not installed on your local computer or the installation is corrupted. You can install or repair the component on the local computer.

If the event originated on another computer, the display information had to be saved with the event.

The following information was included with the event: 

managed-keys-zone ./IN: loading from master file managed-keys.bind failed: file not found

the message resource is present but the message is not found in the string/message table

Regards, Dragon