Your site was unable to contact Apache Solr server
Some days ago I had a similar problem.

I've download the SolrPhpClient in the .zip file and Search API was not able to connect to the Solr Server (I don't know Apachesolr, I don't use it).

But if I download the .tgz version of the client.. it works. I think that in the .zip version there is some problem with permissions.

So: if you've download the .zip version, try the .tgz.

And obviously try also the r60 version, I use it alwyas.