I've had Paid 2TB Dropbox for several years and have never had this issue before. The Excel file is 11.4 MB. After saving the file then deletes after after a few seconds after syncing. Issue has been occurring for about 3 days now. I went to Dropbox Events and restored the file but after a few seconds it is deleted again. I changed the name of the file and put in a new folder but again it deletes after a few seconds. I renamed the file a few times but again it always gets deleted. I turned off Dropbox and there was no deletion so I'm assuming Dropbox is the problem, not Windows. Dropbox support doesn't know thus far. Some contributing factors may include that this file is saved programmatically and the file is somewhat large....not sure since I have many other large excel files with no issues and other files that are saved programmatically also.