In what release were the P-coded files created? The documentation page for the pcode function states "The pcode algorithm was redesigned in MATLAB version R2007b. If a P-file was generated prior to R2007b, then it will not run in versions R2015b or later. Files generated in R2007b or later do not run in R2007a or earlier."
If the P-coded files were generated in release R2007a or earlier, they will need to be regenerated.