You will be able to use pro features in the ONLYOFFICE Desktop Editors after connecting to the paid ONLYOFFICE cloud and creating a new document or opening an existing one.
The possibility to enable pro features is available for any paid solution: ONLYOFFICE cloud or server version, or Document Server connected to Nextcloud/ownCloud.
Connecting to the cloud
To connect to the ONLYOFFICE cloud:
- Launch Desktop Editors.
- In the main program window, switch to the Connect to cloud tab at the left sidebar.
- Click the ONLYOFFICE button.
- Specify your web office address in the new window.
- Click the Connect now button.
- On the authorization page, specify the login and password used to access your cloud office account.
Creating or opening a document
Once you connected to the ONLYOFFICE cloud, select the necessary section and folder in the Documents module and open the necessary document or create a new one.
To open an existing document, click on its name in the document list.
To create a new document, click the Create button in the left upper corner, select the Document option, set the document name and click the Save 
icon.
When you disconnect from the cloud, pro features will still be available in the ONLYOFFICE Desktop Editors and you will be able to use them when working with documents stored on your computer.
If you reinstall ONLYOFFICE Desktop Editors after activating pro features, you’ll need to connect to the paid cloud once again and create or open a document to reactivate pro features.