Empty CSV after automatic upload

Hi everybody,
I'm trying to manage that every day a generated csv stock list will be automatically uploaded to an FTP server. The uploaded is working fine, but the uploaded CSV file is empty and has 0 kb.
If I open the local file it's not empty and after making manual changes and save the file the upload starts again, and it's not empty on the FTP anymore.
Is it possible that the upload starts to early while the original CSV isn't ready? Can I make a timer for waiting if there is a new file before uploading?

Thanks in advance.

Sorry, but you didn't tell us how do you trigger the upload. So we cannot tell you how can you delay that trigger.