An error occured during the script execution: Feature was null

Setup, Configuration and Use Scripts & Rules
1

Hi all,
I am new to openhab 2. I want to start with a simple rule but even this does not work.
Here is my rule:

rule "open rollershutters"

when

    Time cron "0 53 11 * * ?" <- 06:30:00 Monday to Friday

or

    Time cron "0 30 08 * * ?" <- 08:30:00 Saturday & Sunday

then

    sendCommand(SZ_ACT_ROLLO_NORDEN, UP)

end

In the logs I get the following error:
Error during the execution of rule open rollershutters: An error occured during the script execution: Feature was null.

Can someone help me here?
Thank you!!

2

I think your comments need preceding with //

Time cron "0 53 11 * * ?"   // 11:53:00 Every day

You do realise the comments do not match the actual cron?

3

Be aware. There is still a bug that two or more crons in one rule doesn’t work. You need a rule for every cron until bug was fixed.

4

Thank you guys! The rule works now.
Do you have experiences in using the Rule Engine?