Hi marco,

Is it possible for you to provide us with the back end and FTP access to your site to check on this issue?

You can add the information needed by edit your first post in the Details section or you can just include your site's access once at http://stackideas.com/dashboard/site rather than needing to keep adding them in your replies

Before that, perhaps can you double check in you file directory:
.../administrator/components/com_easyblog/includes/fields/types/...
Is there any file name as Icon.php
like example
../administrator/components/com_easyblog/includes/fields/types/icon.php ?
if yes, can you delete(or backup it somewhere else) the file, it should fix the issue.
If by deleting it not solve the issue, we probably need your access above to troubleshoot further