Hi!
I want to report that I had the exact same problem. To solve it I’ve launched Rack from cmd (as was suggested previously in this thread) with custom folder location without any non-unicode symbols in its path. So, I’m pretty sure it’s all about your plugins folder path.
My defalut system language is russian so I have “Документы” instead of “Documents” – I guess that’s where the problem comes from.
Is it some string length counting issue? UTF-8 bytes is not the string length.
EDIT: yes, i’ve been Unicoding to UTF+8 as an extension to a 32-bit code point code before it became 20/21-bit max. i even get an occasional email about the standards working group.
EDIT2: The surrogates area is open for unofficial reuse in the UTF-8 standard if the PUA isn’t grande enough. As 16-bit surragate codes have to map to code points before UTF-8 conversion.