I have a 14 year old domain that was affected by the very first round of Panda then last October hit with a -50 penalty.
So I believe the site has a content problem (Panda), the -50 could be related to that as well, or could be a backlinks penalty.
The penalized domain was part of a massive reciprocal link campaign beginning in 1998 and lasting maybe 7 years or more. All on topic reviewed links, but still... Anyway, that practice was stopped and all recip links were dumped several years ago.
If there is a backlink problem I don't think I can fix it. Everything possible to try and fix that was already done years ago.
I can fix the content problem by creating a new type of content which I have done with another site (on a different topic) and it worked with no link building.
I have added a lot of new content to the penalized domain already as well as a lot of general clean up but there has been no improvement.
So what would you do? Keep adding to the domain that has been Pandalized since feb 24 2011 and penalized since last October? Or start fresh?