A: Sometimes, ATS installs point to cache files that are installed relative to the ATS root directory. This is pretty common in test setups right after a basic install. There's not really any way for SCAN to 'detect' when this is happening (though it will try), so the best solution is often just to try running scan from that ATS root directory. For example, if you have a directory /opt/trafficserver that holds all of the trafficserver files, try going to that directory before running scan. A: Congratulations, you've just been drafted! Try running scan like this: scan --debug <other options that you specified last time> 2>scan.err (you may not see the error message this time) and then create a github issue and upload/pastebin/^C^V the scan.err file that should've been created and link/paste it into the box, along with a description of what you were trying to do and what went wrong. I'll fix it as soon as I can.