I caused this problem myself. The error in the myRIO log was "startup application not found"
I was fiddling with settings and changed the Destination path (in the build properties) from
/home/lvuser/natinst/bin
to
/bin
thinking that was the destination path on my PC's HDD rather than the path on the RT disk !!!
I forgot I did that and didn't connect my error to what I did until a few hours of searching.
Peter