1. A method for detecting a first string which does not match one of a plurality of predetermined strings and replacing the first string with a second string which matches one of the plurality of predetermined strings comprising: receiving a string; determining whether the string matches one of the plurality of predetermined strings; and if the string does not match one of the plurality of predetermined strings, then A. determining that the string is the first string; B. receiving an alternate string which matches one of the plurality of predetermined strings; C. comparing the first string and the alternate string using a plurality of difference criteria; D. for each of the difference criteria, if the first string and the alternate string differ according to the difference criterion, then (i) identifying the alternate string as a replacement candidate string for the difference criterion, and (ii) setting one of a plurality of replacement indicators indicating that the replacement candidate string exists for the difference criterion; E. if the replacement indicators from the difference criteria satisfy a selection criterion, then selecting one of the replacement candidate strings identified by the difference criterion as the second string; and F. replacing the first string with the second string.