When a Google Doc file is created (whether in Box or G-Drive), it’s tied to that storage provider. Even though you can download the .gdoc file from box, you can’t upload that .gdoc file to G-Drive and expect to edit the file.
As part of the fix for v2.6.5, transferring a .gdoc file from Box to G-Drive will generate an error and appear in the sync history as an error. This error comes from the Gdrive API, not something we generate. Google will not allow .gdoc files to be uploaded to G-Drive thru their API.
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