My Localizable.strings file has somehow been corrupted and I don't know how to restore it.
If I open it as a Plain Text File it starts with weird characters that I can't copy here.
If I leave the file be the app builds. If I make any changes either the values aren't interpreted properly or I get an error at compile time.
Localizable.strings: Conversion of string failed. The string is empty.
Command /Developer/Library/Xcode/Plug-ins/CoreBuildTasks.xcplugin/Contents/Resources/copystrings failed with exit code 1
I suspect this is an encoding problem but I don't know how it happened (maybe SVN is to blame?) nor how to solve it. Any tips will be much more appreciated.
I have issues with the same file that sound very similar to your own. What happens for me is that Xcode doesn't know the correct file formating. I often get this when rearranging the project and I remove and re-add this file to the Xcode project. When I re-add the file, its encoding gets set to something like Western Roman which can't seem to render anything other than ASCII.
Here's what I do to fix the problem:
In Xcode select the Localizable.stings file in the Groups&Files panel.
Do a Get Info on that file.
On the info panel select the General tab.
In that tab go to the File Encoding and change its value.
The last step is where the trick lies as you now have to guess the right encoding. I find that for most European languages that "Unicode (UTF-8)" works. And for Asian languages I find that "Unicode (UTF-16/32)" are the ones to try.