Error: "invalid command name" when running a Tcl script that uses Tk widgets - Error: "invalid command name" when running a Tcl script that uses Tk widgets Description Beginning with the Quartus ® II software version 2.2, you may receive this error if you use Tk widgets in a Tcl script, because the software does not automatically initialize the Tk toolkit. To avoid this problem, add the command init_tk at the beginning of any Tcl script that uses Tk widgets Custom Fields values: ['novalue'] Troubleshooting novalue False ['novalue'] ['novalue'] novalue novalue ['Programmable Logic Devices'] ['novalue'] ['novalue'] ['novalue']