What are some ways to prevent data fishing?

[Bob Dole]

Suppose you have a data file in your protected software (assume it's protected by something like VMP or Themida) that you don't want a user to tamper with.  You conclude that you will embed information into this data file which your program will use, i.e., initiate constants using this data as some kind of initial value. However, this can be bypassed relatively easily if the cracker (a) knows you're doing this to a specific data file and (b) can debug your program to fish out these constants.  Then simply replaces your data file and writes a loader to overwrite these constants with the fished data.

Is there anything that can be done to make this even more difficult for the cracker to replace?

Edited October 16, 2017 by Bob Dole