Why do I always get "Communication Failure"?

Question

I always get "Communication Failure" error. I have changed USB connection cables between UPS and PC, computers with different versions of Windows (XP, 8.1), Firewall off. But no response, the problem still exists.
Any suggestion?

Answer 1

You have to change some settings in UPSmart if you keep receiving the Communication Fail error. I've downloaded the PDF guide and it appears that it provides some insight into the different configuration methods regarding connectivity.

I recommend downloading the PDF file from the following link to check the mentioned settings.

Answer 2

I am running Ubuntu, and the software just does not connect.

Answer 3

For a Ubuntu install a udev rule was needed

This is a sample udev file for HIDAPI devices which changes the permissions

to 0666 (world readable/writable) for a specified device on Linux systems.

If you are using the libusb implementation of hidapi (libusb/hid.c), then

use something like the following line, substituting the VID and PID with

those of your device. Note that for kernels before 2.6.24, you will need

to substitute "usb" with "usb_device". It shouldn't hurt to use two lines

(one each way) for compatibility with older systems.

HIDAPI/libusb

SUBSYSTEM=="usb", ATTRS{idVendor}=="0001", ATTRS{idProduct}=="0000", MODE="0666"

If you are using the hidraw implementation (linux/hid.c), then do something

like the following, substituting the VID and PID with your device. Busnum 1

is USB.

HIDAPI/hidraw

KERNEL=="hidraw*", ATTRS{busnum}=="1", ATTRS{idVendor}=="0001", ATTRS{idProduct}=="0000", MODE="0666"

Once done, optionally rename this file for your device, and drop it into

/etc/udev/rules.d and unplug and re-plug your device. This is all that is

necessary to see the new permissions. Udev does not have to be restarted.

Note that the hexadecimal values for VID and PID are case sensitive and

must be lower case.

If you think permissions of 0666 are too loose, then see:

http://reactivated.net/writing_udev_rules.html for more information on finer

grained permission setting. For example, it might be sufficient to just

set the group or user owner for specific devices (for example the plugdev

group on some systems).