Roshal (autor WinRARu) tvrdi, ze je to dane pouzitim DLL, ktera se oficialne distribuuje pro 7z format a momentalne s tim nemuze nic moc delat:
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I am not sure if it can be improved on WinRAR side. Maybe I'll
check it
later, but chances are not high.
WinRAR uses 7zxa.dll library provided by
7z developer to decompress
7z archives and usually WinRAR just redirects
password requests generated
by this library. It is not safe for WinRAR to
ignore a part of such
password requests, because 7zxa.dll is expected to know
better how many
passwords are needed for archive.
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