I should be a MiKTeX misconfiguration, I guess. I have no access to a windows operating system to try MiKTeX but with TeXlive, I have got no problem. v1.0.7 is not the latest version of bidi. The latest is 1.0.9 and TeXlive already included that. The only difference is that from .../xelatex it is moved to .../latex as it now supports Plain TeX and LaTeX and it requires another package, iftex which is a very small package for XeTeX, PDFTeX and LuaTeX conditionals. I suggest contacing MiKTeX's author.
-- Best wishes, Vafa Khalighi
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