Hi Michel,

Follow these general steps to convert a user with a Community licence to a Salesforce Platform licence:

1) As a user with the System Administrator profile or a profile with the required permissions, log into your Salesforce organisation.

2) Go to Setup (tool icon in top-right corner) and choose "Setup" from the dropdown menu to see the user's profile settings.

3) Click "Manage Users" and then "Users" in the "Administer" section of the Setup page's left sidebar.

4) Identify and select the person whose Salesforce Platform licence you want to update.

5) Click the "Edit" button located on the user's detail page.

6) Choose a profile that has a Salesforce Platform licence assigned to it by going to the "Profile" section. You might need to establish a new profile or edit an existing one to add the required permissions and licence if you don't already have one.

7) To save the changes, click the "Save" button.

The user's licence should be changed to the Salesforce Platform licence once you've finished these procedures. Keep in mind that Salesforce licences are limited, so if you've used up all the licences your organisation is permitted to have, you could need to buy more.

Please mark as Best Answer if above information was helpful.

Thanks,