/dev/ttyUSB0 - minicom problem

[Dino]

hi all,

i don't have serial ports on my laptop, so i'm using a USB to serial
converter.
i installed minicom and everything seemed to work fine. but there are
still 2 problems:
1. when i exit minicom and then try to start again another session,
bash tells me something about a locked file, i assume /dev/ttyUSB0.
2. when i exit minicom, unplug the USB cable and plug it again in the
port, my usb-mouse stops working.
Any help?

thanks,
Dino