I have an old asp.net app that uses the project.asmx service of an old project server, which is being upgraded to project 2016. The calls that work fine against the old server fail on the new server with a message of
"Unhandled Communication Fault".
The ULS logs on the SP box show an exception of
"unhandled exception in the WcfPsiRequestRouter...Incorrect inproc routing. No inproc host is available for project".
Other posts suggest that there could be difficulties with claims auth, though a few lines in the ULS log above the error message are a few success entries showing that the user was authenticated and "successfully got user key for user".