Optimization of Program for use on Severl Computers

[JElias]

I am new to LabView and this forum and am hoping that I may be able to setup an existing LabView program for increased versatility. The existing program has many references to a specific drive letter on the current computer that it's installed on. What I wish to do is make this drive letter changeable depending on the main drive of the computer. So far I have built a subVI that will read in the existing file name and removed the drive letter then replace it with whatever drive letter is in a path control box presented in the main VI front panel. The problem I am having is to connect the subVI that I have created with the existing VI and all of its subVI's. I believe that I have to use global variables but all I get is error messages when trying to build the block diagram (i.e.: message stating that two different types have been connected, path and void). Any ideas of how to modify the file type or make this program work would be greatly appreciated.

Jordan