Does your username have any special characters in it? Ligatures (ij), diacritics (š), spacing modifiers (ʰ), non-Latin alphabet (ӝ), punctuation (※), symbols (∉), Right-To-Left characters etc.?
If it does could you please give me some examples of the special characters it contains?
Finally, as a test, could you please create the folder C:\SFCFixTest (or something similar), place the .zip script and .exe file and try running SFCFix from there?