Internal server error, old attachments disappeared

I have a site in test. Upgrades EG-Attachments some days ago to version 2.0, i’ve found some problems:

a) In old pages, all attachments are disappeared.

b) When i try to put a new attachment, i receive this message:

‘Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.
Please contact the server administrator at [email protected] to inform them of the time this error occurred, and the actions you performed just before this error.
More information about this error may be available in the server error log.’

I put attachments through the button in the editor.

As a reply to another similar topic, i haven’t activated tags for attachments in EGA->Settings

href=”http://www.istitutocomprensivoiozzelli.gov.it/test/”