1/ You need correctly installed 3.40.27 or 3.41rc1.10+ (if you have 3.40.27 installed, you can create copy this folder for use to install 3.41rc1.12)
2/ Delete folder "plugins" in your installed folder B738X
3/ Install patch 3.41rc1.10
Release note - fixed bugs:
- engine starter switches
- RTO knob
- Landing altitude knob - step 50ft
- electric systems (powered bus in cold&dark state)
- APU air bleed
- GPWS Test
- Audio panel (volume/selector)
- fuel pumps
- acf files (thanks to MaxNGX)
- pressurization system
- LAND ALT, CRUISE ALT knobs - repeat command
- warning for use illegal commands in Xplane
- smooth brake command
- trim sound issue
- reverse engines code
- steering code