Error when upgrading 1.9.1 -> 2.0.4 : duplicate entry

Hello,

I have this error

Duplicate entry '18' for key 'PRIMARY' SQL=INSERT INTO `****_comprofiler_plugin` (`id`,`name`,`element`,`type`,`folder`,`viewaccesslevel`,`backend_menu`,`ordering`,`published`,`iscore`,`client_id`,`checked_out`,`checked_out_time`,`params`) VALUES (18,'CB Forums','cbforums','user','plug_cbforums',1,'',9,1,1,0,0,'0000-00-00 00:00:00',''), (19,'CB Blogs','cbblogs','user','plug_cbblogs',1,'',10,1,1,0,0,'0000-00-00 00:00:00','')

when I try to upgrade from cb 1.9.1 to cb 2.0.4 (joomla! 2.5.28).

When I look at the cb tools, tables are right.

What would I do ?

Thanks