Hi @bodyfix,
try to use 1.9.0 or 1.11.0 version, since 1.10.0 is broken for some reason. I got some days ago follow PM
Kind regards,
Alexander
EDIT: If you use openhabian, may be you run into: GPIO Binding not working · Issue #39 · openhab/openhabian · GitHub
EDIT2: Take a look here: Org.openhab.binding.i2c or org.openhab.binding.mcp23017