Fails to install, can't find `jupyter` on 18.04

Hi all, I’m having trouble installing on Ubuntu 18.04.1 LTS. The installer can’t find the jupyter script in the install location—any thoughts?

Here’s the output from the installer (n.b., this is me rerunning the installer, as a result it says TLJH already installed).

Checking if TLJH is already installed...
TLJH already installed, upgrading...
Upgrading TLJH installer...
Setup tljh package
Starting TLJH installer...


==> WARNING: A newer version of conda exists. <==
  current version: 4.5.8
  latest version: 4.5.11

Please update conda by running

    $ conda update -n base conda


Traceback (most recent call last):
  File "/usr/lib/python3.6/runpy.py", line 193, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.6/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/opt/tljh/hub/lib/python3.6/site-packages/tljh/installer.py", line 445, in <module>
    main()
  File "/opt/tljh/hub/lib/python3.6/site-packages/tljh/installer.py", line 433, in main
    ensure_jupyterlab_extensions()
  File "/opt/tljh/hub/lib/python3.6/site-packages/tljh/installer.py", line 172, in ensure_jupyterlab_extensions
    ] + extensions)
  File "/usr/lib/python3.6/subprocess.py", line 336, in check_output
    **kwargs).stdout
  File "/usr/lib/python3.6/subprocess.py", line 403, in run
    with Popen(*popenargs, **kwargs) as process:
  File "/usr/lib/python3.6/subprocess.py", line 709, in __init__
    restore_signals, start_new_session)
  File "/usr/lib/python3.6/subprocess.py", line 1344, in _execute_child
    raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: '/opt/tljh/user/bin/jupyter': '/opt/tljh/user/bin/jupyter'

[hMED22]

I had this problem and solved it like @dgot said but than had another problem launching the server, using sudo journalctl -u jupyter-<name-of-user> I found that an Import error was raised for a package that I had installed in my local python environment but not in /opt/tljh/user/ environment. but when I tried to install it:

source /opt/tljh/user/bin/activate 
sudo -E /opt/tljh/user/bin/pip install package

I got Requirement already satisfied: package in /home/username/.local/lib/python3.6/site-packages I believe that that’s what happened when the tljh installer called conda.ensure_pip_packages. Finally the thing that fixed it is using -H flag with sudo, so to fix this issue one could use:

source /opt/tljh/user/bin/activate 
sudo -EH /opt/tljh/user/bin/pip install jupyter

[jhadjar]

Thank you, dear colleague : ) This should teach me to read the README.md