Error #75 at Open {file} For Input As #1 (need 2 progs on same PC to communicate)

[Kernelpanic]

This now reminds me of MySQL and PostgreSQL; that I once had to do with. The file that is currently being written to must of course be locked for other write access. . . otherwise there would be breakage.

This is all very complicated. And therefore very error-prone.
@madscijr, check the design of your program again.