How to fix "containing working copy admin area is missing" in SVN?

I deleted manually a directory I just added, offline, in my repository. I can't restore the directory.

Any attempt to do an update or a commit will fail with:

"blabla/.svn" containing working copy admin area is missing.

I understand why, but is there anyway to fix this.

I don't want to checkout the entire repo and add my changes to it manually, it would take hours.

According to this: http://www.devcha.com/2008/03/svn-directory-svn-containing-working.html

Check-out the folder "blabla" to a different location and then copy its .svn folder back into the original "blabla".

fwiw, I had a similar situation and used svn --force delete __dir__. That solved the issue for me. Then i continued working with my working copy as normal.