obfs4proxy causes issues on Windows with certain AV products.

From the Tor Browser 4.5-alpha1 post:

my system was crashed and shut down when i Run obfs4 transport!!! also my antivirus acted (Bitdefender)

win 7/ultimate 32 bit

I don't have BitDefender, and I verified that obfs4proxy works on:

  • Windows 7 Professional (32 bit)
  • Windows 8.1 (64 bit)

As other people also report that it works fine, for now I assume this is a weird AV false positive/interaction, but further research is needed.

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