You have come across this error svn: Directory .svn containing working copy admin area is missing the reason is simple. You have deleted the .svn directory (probably not on purpose).
I regularily have seen this issue arise when working with build scripts where directories that are built on the fly and are checked in. Dynamicly created directories are best left out of version control.
So what to do? You can check out the directory again into a new temp folder and then rename or mv the folder to the correct.
svn co http://svn/project/trunk/originaldir temp mv temp originaldir
On a windows system you would do the same check out the original directory into a temp and rename the temp directory to the original directory name.
It is also possible to check out the whole project again which would only be necessary if multiple .svn folders are deleted.
