It looks like your solr lucene-core version doesn't match with the lucene version used to generate the index, as Yonik said, looks like there is a lucene library conflict.
2009/8/19 Chris Hostetter <hossman_luc...@fucit.org>: > > : how can that happen, it is a new index, and it is already corrupt? > : > : Did anybody else something like this? > > "Unknown format version" doesn't mean your index is corrupt .. it means > the version of LUcnee parsing the index doesn't recognize the index format > version ... typically it means you are trying to open an index generated > by a newer version of lucene then the one you are using. > > > > > -Hoss > > -- Lici