Can't upload files using Omeka.net

I'm trying to build a site with an omeka.net hosted account. When I try to upload a file I get "File Upload: File 'file_0_' can't be written".

I initially tried uploading a jpg < 10 KB, but it doesn't matter which browser or file type I try, I still get the same error.

Thanks in advance.

Nevermind, resolved.