ive just got hold of my canems usb adaptor that works on all other ecus my leads giving me a comm port 7 or 8 depending on which usb i plug it in but the vems wont connect to it on megatune help really frustrating
If its changing the com port depending on the USB port then you have a problem with the drivers.
Uninstall all the USB to COM port drivers and start afresh.
ok mate il try that now
says my comm ports 3 4 5 6 are taken so ive assinged it to 1
managed to get it connected today and tried it a second time and cant get it to connect on the vems tune or mega
sounds to me like you have bad ground or wires touching inside the db9 plug.
check you wiring to the db9. make sure you do not have a fault in the wiring.