You can export files for offline translation. Once translated you can import them again and Pootle will manage updating the translation in Pootle based on your changes.
This feature is ideal for teams who have poor connectivity or if you prefer to use an offline translation tool.
To export, simply click on the “Download for offline translation” link on the sidebar in Pootle’s overview page. To import simply click the “Upload translations” link and select the file you wish to upload.
Warning
If there are any errors in the upload then Pootle will warn you and the file will be rejected.
The most likely reason would be someone translating online while you are working offline. So be sure to communicate with your team if you will be working offline.