I can right click any folder tied to SVN and say "Show log" it works. If I do the same thing for a file it says dir/subdir/subsubdir/default.aspx path not found error.. I couldn't figure out why..
My Solution: clear svn caches. (TortoiseSVN | Settings | Saved Data) I used Win 7, TortoiseSVN 1.7.9
I had the same (as far as I understand) problem: Svn log (TortoiseSVN | Show log) returned a "path not found" error message for a specific file from my working copy. The problem could be reproduced using the repo browser. Svn update and even commit worked fine for that file from my working copy. Svn log (update/commit) on other files in the same folder worked fine from my working copy. My colleagues didnt have problems at all.
And yes: My Working copy was cleaned up, up to date and bound to a valid URL. The server was accessible via pasting URL to browser etc.
As I had the problem using the repo browser I never thought local (cached) data could cause the problem...