massively grateful for your time, effort and replies
having established that guitarport was definitely working fine, had another go connecting to mac
plugged in guitarport opened gearbox failed to open (code 80000003) could not create a thread
tried to open gearbox again, gearbox opened but still not connected
have always closed gearbox with macs red stop button, for some reason clicked on gearbox's on/off switch next to tuner
error could not enable/disable bypass reason: (code 8000740D) cannot access hardware device
so closed with red stop button as usual
triryche the link you added was certainly relevant enough to make me realize that
although i thought i had deleted all line 6 files before reinstalling i clearly hadn't.
merely trashing all visible files obviously leaves hidden files behind
so decided to have another go at deleting / re-installing but this time more thoroughly
first step, applications / line 6 / drivers. this folder don't contain drivers, contains line 6 driver uninstaller
uninstalled drivers. restarted. thought i might as well have a go at reinstalling drivers and giving it a go
there you go, all sorted, it was that easy
guitarport fully functioning plugged in x3live yes also fully functioning
the real zap "To remove driver 7.3.6"
your way ahead of me i'm still on 7.1.9
it is an intel mac, operating systems are like women newer versions come along sleeker more attractive which function better
but ultimately no less complicated, so after years of trying to work them out, i'm happy to stick with what i got.
once again a big thank you for your time and effort
very much appreciated tony