As with any web-based software, there are occasionally glitches of this type. The best way to troubleshoot is to first try uploading the file again. If it still does not work, log out, close your browser window, and delete the cache and if necessary. Log back in and try again.

Clear cache and cookies in Chrome:

1. Click the Tools menu (three dotted lines in the upper-right corner).
2. Select History.
3. Select Clear Browsing Data from the left-hand side. Set the Time Range set to All Time. Check-mark Cookies and other site data and Cached images and files and select Clear Data.

Delete cache and cookies in the new Microsoft Edge

1. Open Microsoft Edge, select Menu (3 dots icon on the top right corner of the browser) > Settings > Privacy & services.
2. Under Clear browsing data, select Choose what to clear.
3. Select "Cached images and files" and "Cookies and other site data" check box and then select Clear.

Note: Larger files take additional time to upload. 

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