Message Oracle NNL-00022 - error changing trace level from string to string, level change ignored

ERRORerror changing trace level from string to string, level change ignored
CAUSEThe user attempted to change the control programs local trace level, and the program encountered an error while changing the level. Usually the problem is that tracing was enabled for the first time (by changing the trace level from OFF to something else) and the trace file is not writeable by the control program.
ACTIONCheck to see that the trace file is writeable. Your documentation will tell you the name of the trace file.