This section lists common problems and possible solutions. If you experience other problems or would like to add a solution for a problem feel free to open an issue in our Github project or send us an email to

Permission denied when accessing the USB-Mux

Problem: The control software outputs an "Access denied" message and does not find the specified USB-Mux.

In the following example a user tries to access the USB-Mux without previously installing the udev-rule:

$ usbmuxctl --serial 22 status
Access denied while checking serial number for device: 1-5.1
Failed to connect to device: Failed to find the defined USB-Mux

To fix this issue either run the tool as root (e.g. using sudo) or setup an udev-rule that grants access to your user. The chapter Using as non-root user for setup instructions. Make sure to reload the udev config, re-attach the device and re-login into your device after installing the rule. Also make sure that the group name specified in the udev rule appears in the output of the groups command:

$ groups
… plugdev