If your MSTS/OR installation is on the H drive, there should be nothing related to either program on the C drive. The shutdown is being caused by OR hanging in the sound process, so that is where your problem lies as explained by mikebb. As for files missing when transferring from an external SSD to an internal drive, I suspect that the crash has damaged that SSD, so files are also damaged and will not transfer. That has nothing to do with Win 10.
Or will not look for anything on the C drive unless you have a mini route folder there and you add it to the OR list of locations.
Beer is not a matter of life or death, it is much more serious than that.