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When I try to specify a crypto mode for Synergy on the command line using --crypto-mode, I now get this error:

Unrecognized option: --crypto-mode

How do I solve this?

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up vote 5 down vote accepted

In our 1.4.13, we dropped the --crypto-mode arg, since we removed all crypto modes except CFB. So right to solve this, just don't use the --crypto-mode arg.

We added this arg in version 1.4.12 - it was so that users could in theory add an extra level of randomness to make a hacker's life harder. However, this was a bad idea for a few reasons:

  1. Security by obscurity is not a good cryptography practice.
  2. 3 of the 4 crypto modes were easily cracked.
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