There must be a setting in Avast! to let Poser and AIR communicate properly.  Sometimes, that's the issue with all-in-one do-everything security suites.  I used Avast! a LONG time ago.

Currently I run MS Security Essentials, have Malwarebytes (free), and I run Panda Online Scanner manually on occasion.  I also run Adblock Plus and NoScript in FF and try to carefully select what comes through.

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