Security
An access key is needed to access the REST API from outside the Planon application. But access keys can only be generated if the Planon software allows us to do that.
Procedure to allow generation of access keys:
1. In the navigation panel, go to System settings > Security.
2. Click the Key pairs tab
3. The setting Access key generated? should have value Yes.
If it has value No, click on Generate key pair in the action panel. That should change it to Yes.
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If the setting Access key generated? was already set to Yes and the action is triggered anyways, all existing access keys become invalid.