I made a clean reinstall of the 757 as admin. (deleted old folders etc.)
Still the autobrakes switch to disarm when the main gear touches the ground´.  :-[
My FSX install is quite new too (Win 7 64-bit) and i got no aircraft of other developers installed. Only the 727 & 767.
Anyone got a idea what to try?

Edit: Just tested the 767-300. Its the same. The autobrake disarms on touchdown.

Greetings
Nepo