Yes, you are right. The Retry Attempts and Retry Interval option from agent job relys on the failure of package execution and it will record every failure of retry in log. So if the source file is existed but is still in the process of being written, the uploading package will be failed anyway. That just takes the step of the job waiting for a next retry and that's it. I think the file size is quite unreliable to be taken as judgement. 1K means an empty file (it's ok to me. that means no new record today), but how big the size means good file and will that be accurate? Actually, I developed a custom task component to check the file existence (similar code but in C##). It can be used in any package that I want to check the file existence. All I need to do is to pass the full path file name as the parameter to that component. That works prety well for me.