Yasin Karanfil

If Subclipse complains about this error

Path is not a working copy directory
svn: '[original (pre-move) directory path]' is not a working copy

Doing things outside of Eclipse is more likely to create problems than solve
them.

To delete the cache, close Eclipse. The cache is stored in:
[workspace]/.metadata/.plugins/org.eclipse.core.resources/.projects/PROJECTNAME/.syncinfo

So you can just find and delete all files named .syncinfo in
[workspace]/.metadata/.plugins/org.eclipse.core.resources/.projects.

source:http://subclipse.tigris.org/ds/viewMessage.do?dsForumId=1047&dsMessageId=868799