Please follow these guidelines for uploading content (metadata and reference files) to Google.
Create a unique folder for each upload batch
All files that you post to your dropbox must be in a folder. Google ignores files in the root folder of the dropbox, including any delivery.complete files.
To avoid possible naming conflicts, we recommend that you create a new folder each time you post content and that you include a timestamp or incremental ID in each folder’s name. The timestamp or ID provides a good way to track the upload batches.
Use smaller batches
Create multiple smaller batches rather than a single larger batch. We generally recommend uploading the files for one asset at a time. If you’re using a dropbox, create a separate directory — and separate delivery.complete file — for each asset.
It doesn’t take any longer to process 10 batches containing one asset each than one batch containing 10 assets. The processing of each individual batch is faster, though, and any failed uploads affect only the problematic asset.
The recommended maximum size for an upload batch is 100 assets. The metadata file (CSV or XML) cannot exceed 10MB.
Include all referenced files
Make sure that the file names referenced in the metadata CSV or XML file match the actual files you’re uploading, including their file extensions. The upload will fail if the names don’t match or if a referenced file is missing.
Remove the folders for successfully uploaded batches from your dropbox
Your dropbox is a temporary staging area for uploading content. It is not intended for long-term storage. We automatically remove files that have been in your dropbox for more than 45 days. We recommend deleting the folders and status files for successfully uploaded batches.
The failed_packages subdirectory of the dropbox account contains files that we were unable to upload successfully. Review the files to correct the issues that prevented proper uploading, then move them to the folder for a new upload batch. We will process the files again when you add the delivery.complete file to the folder.