When using the Upload/Download program in Qlik Gold Client to perform a config upload, it is possible that the error "Unable to read file using GUI_UPLOAD method” may occur.
The primary reason for this result is because the selected file path-filename length is too long for the ‘Local path and filename field’ which is limited to 120 characters.
The solution is to move the file to a directory having a shorter file path and/or to shorten the filename. If this recommended action does not resolve the error, submit a support case to the Qlik team for assistance.