Arduino Uno with Kubuntu 16.04: Unable to enumerate device I try to connect my arduino uno R1 in order to program the atmega8u2 but I am not able to do so. When I run sudo dfu-programmer atmega8u2 erase I get the following results:

dfu-programmer: no device present.


So in order to diagnose it i run dmeesg with the following results:

 [ 1395.921051] usb 2-3: new full-speed USB device number 30 using
 xhci_hcd [ 1396.041175] usb 2-3: device descriptor read/64, error -71
 [ 1396.269135] usb 2-3: device descriptor read/64, error -71 [
 1396.497109] usb 2-3: new full-speed USB device number 31 using xhci_hcd [ 1396.617169] usb 2-3: device descriptor read/64, error -71
 [ 1396.845177] usb 2-3: device descriptor read/64, error -71 [
 1397.073163] usb 2-3: new full-speed USB device number 32 using xhci_hcd [ 1397.073371] usb 2-3: Device not responding to setup
 address. [ 1397.281311] usb 2-3: Device not responding to setup
 address. [ 1397.489086] usb 2-3: device not accepting address 32,
 error -71 [ 1397.609173] usb 2-3: new full-speed USB device number 33
 using xhci_hcd [ 1397.609382] usb 2-3: Device not responding to setup
 address. [ 1397.817200] usb 2-3: Device not responding to setup
 address. [ 1398.025176] usb 2-3: device not accepting address 33,
 error -71 [ 1398.025235] usb usb2-port3: unable to enumerate USB
 device


Do you know fellows how to make my arduino connect back into my computer?

Furthermore II forgot to mention my user is in dialout group as groups gnu/linux command mentions:

pcmagas adm dialout cdrom sudo dip plugdev lpadmin sambashare libvirtd docker wireshark


PS: That thing happened after soldering the resistor into the board so it is a new problem.
You should solder the resistor (in case you do not have the skills I reccomend doing into a proffessional, a professional close to me managed to solder it with a cost about 5 euros) and then hardware reset the atmega8u2 the documentation mentions. For quick reference just look over in this image:



In the dmesg you will see similar the same or message:

[ 1544.679504] usb 1-6: new full-speed USB device number 42 using xhci_hcd
[ 1544.808341] usb 1-6: New USB device found, idVendor=03eb, idProduct=2ff7
[ 1544.808350] usb 1-6: New USB device strings: Mfr=0, Product=1, SerialNumber=0
[ 1544.808356] usb 1-6: Product: Arduino Uno DFU


Then look on the similar question for R1 boards or in case you have a newer board then follow the instructions mentiones to the documentation.