Hi,
While reply from rraghvani is correct and can be used for your case, the case itself rises a couple of questions.
Is it really necessary to wait until the file is processed? Will your actual user wait for this? Is it possible to upload several files and check later if all of them were processed? Can your file or backend business logic be modified/simplified to make the (specially marked test) file to be processed immediately?
If nothing from above is not an option, remember that parallel tests execution is not supported in TestComplete. This means that your test and the whole test box will effectively be blocked for 30 mins while waiting for 'Completed' to appear.
You and your developers may consider to issue some event when file processing is over and let TC know about this - https://support.smartbear.com/testcomplete/docs/testing-with/advanced/handling-events/creating-handlers/for-external-com-objects.html for more details.
AlexKaras has the right idea. I'm wondering what you are actually testing?
If you are testing the download to make sure it will handle large files, do this once and not every time you run the test. There's no need to retest with a large file unless the download function actually changes. Put a small file in for everyday use.
If you are putting those files out for a following test to use, consider just putting the files out and leaving them where they need to be while you are testing. Update them manually if you need to.
What scenario are you actually testing with this?
