I've tried your suggestions and the program still stalls at the same point. As for the "$count =((...." line, that's probably the only part of the program that I'm sure is working properly. The $count variable takes the form of "1" if a change is made and stays null if no changes are made. If a match is found, the $change variable copies the $_ variable and then all of the $change variable characters are replaced with 00s. I think that there is some kind of conflict between the loop and the promptUser subroutine. I've tried using the promptUser command within a while loop and a foreach loop and it only works once in each of them and then stalls. However, the promptUser command works fine outside of a loop. Where is the conflict? Why is this happening?