Download Attachments Warning in Admin

No response. Hm, I guess this plugin is not supported anymore. Her are some more errors:

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Warning: The magic method Download_Attachments::__wakeup() must have public visibility in /customers/0/a/1/holyriders.no/httpd.www/wp-content/plugins/download-attachments/download-attachments.php on line 106 Warning: Cannot modify header information – headers already sent by (output started at /customers/0/a/1/holyriders.no/httpd.www/wp-content/plugins/download-attachments/download-attachments.php:106) in /customers/0/a/1/holyriders.no/httpd.www/wp-admin/includes/misc.php on line 1431 Warning: Cannot modify header information – headers already sent by (output started at /customers/0/a/1/holyriders.no/httpd.www/wp-content/plugins/download-attachments/download-attachments.php:106) in /customers/0/a/1/holyriders.no/httpd.www/wp-includes/functions.php on line 6935 Warning: Cannot modify header information – headers already sent by (output started at /customers/0/a/1/holyriders.no/httpd.www/wp-content/plugins/download-attachments/download-attachments.php:106) in /customers/0/a/1/holyriders.no/httpd.www/wp-includes/pluggable.php on line 1435 Warning: Cannot modify header information – headers already sent by (output started at /customers/0/a/1/holyriders.no/httpd.www/wp-content/plugins/download-attachments/download-attachments.php:106) in /customers/0/a/1/holyriders.no/httpd.www/wp-includes/pluggable.php on line 1438
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And if you try to activate this plugin you get something like this (Google translated):
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The extension generated 213 characters of unexpected output during activation. If you notice “headers already sent” messages, issues with syndication streams, or other issues, try disabling or removing this extension.
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