Question: is the error string ALWAYS specifically begin with, 'INVALID ORDER ...', or are there other error messages, too? If other kinds of errors may appear (with or without a leading /path/and/filename), then I would recommend grep's solution -- remove the offending path, leaving the rest.

Of course, if the ONLY error message you will get ALWAYS starts with 'INVALID ORDER ', then the solution can be made even less prone to mismatches (just take 'INVALID ERROR ' and anything that follows it):

<CODE> s/(INVALID ORDER .*)$/$1/;

dmm

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