Hello, 

You may use 'Form validation' plug in: http://plugins.glpi-project.org/#/plugin/formvalidation

Regards 

Tomolimo  

@Nicolas: did you vote for this feature?

In English please!

Please post this kind of request on the Forum: http://forum.glpi-project.org

Here, this area is dedicated to new feature request only.

Thank you,

Tomolimo

In English please!

And also that can help to create tickets

My idea is to alert in ajax and then block the submit as long as the chosen time slot is not available for the tech.

Hello,

It should be an alert directly in browser before pressing 'Save', so that users will not be frustrated, and will be able to change the schedule before saving.

Regards,

Tomolimo

In English please!

Hello,

We have the same issue, and we solved it using entities.

Regards,

Tomolimo