You might have had the following error in your dbus daemon at some point and said to yoursefl WTF???

process 1288: arguments to dbus_message_set_error_name() were incorrect, assertion "error_name == NULL
   || _dbus_check_is_valid_error_name (error_name)" failed in file dbus-message.c line 2900.

Well, you are not the only one and I might be able to point you to the correct direction, your code is probably returnning a QDBusError that you created using the QDBusError::Other enum. The problem here is that the enum value your are using only indicates that the error name is not known and therefore cannot be match to a value in the QDBusError enum. When you use that enumerator the message created does have an incorrect name as follows:

QDBusMessage(type=Error, service="", error name="other", error message="msg", signature="", contents=() ) 

And “other” is, of course, not a valid DBus name and thefore the app crashes. Easies way to solve it, create a correct DBusError ;)

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