Similar to this issue when I install the Octopus CLI on the build agent using your OctoInstaller@4 build task I receive the following error:
/opt/hostedtoolcache/octo/7.4.3185/x64/octo: Permission denied
As per the link above if I grant execute permissions on the file then everything works. I’m guessing this is still an issue with your OctoInstaller@4 build task?
Thanks in advance!