Thanks for your response, Joel. I changed the parameter of the file-storage instance under sitemap, unmounted/mounted the instance, even rebooted. Still, no success!
Specifically, I get following error message while uploading a 2.5MB zip file to one of the course public folders.
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We had a problem processing your entry:
* Your file is larger than the maximum file size allowed on this system (2,000,000 bytes)
Please back up using your browser, correct it, and resubmit your entry.
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Am I missing something obvious?