Newbie Can't get cron job to run

Where am I going wrong please?

I see a couple of problems:

1. You're missing a space between the final asterisk in the schedule and the first character of the command
2. Your file is has no line endings.

You can fix both problems with the following command:

echo "`sed 's/\*\/u/\* \/u/' crontab.txt`" > crontab.txt

Also, with the above timings I hope to run the routine at 0,10,20.... mins past the hour. Will this happen or might it run at 02,12,22... mins past the hour?

The schedule above will run at 10 minute intervals, starting at :00 and every 10 minutes thereafter.

I had a similar issue running in 2.7 from crontab: ended calling a script in the same directory as my app. This is what I'm doing (mostly unoriginal work which I probably I cobbled together from answers here on stackexchange).

#!/bin/bash
#set env variables
export ENV_VAR={{whatever}}

mkdir -p "$HOME/tmp"
PIDFILE="$HOME/webapps/{{app_folder}}/{{app_name}}.pid"

if [ -e "${PIDFILE}" ] && (ps -u $(whoami) -opid= |
                           grep -P "^\s*$(cat ${PIDFILE})$" &> /dev/null); then
  echo "Already running."
  exit 99
fi

#now call the actual app
$HOME/webapps/{{app_folder}}/{{app}}.py

echo $! > "${PIDFILE}"
chmod 644 "${PIDFILE}"

I then call the script from crotab thusly:

0 /3 *  * $HOME/webapps/{{app_folder}}/{{shell_script}}.sh > $HOME/logs/user/comm.log 2>&1

Ended up working out better because with the limited env run by cron I needed to initiate some env vars before i called python anyway. hope this helps