This is caused when the data being uploaded is greater than what is specified for AspMaxRequestEntityAllowed.
Solution:
Open your metabase.xml, which is located in 'c:\Windows\System32\Inetsrv', find the line "AspMaxRequestEntityAllowed" and change it to a value to suite your needs.
Note: Editing the metabase.xml file requires shutting down of IIS before you can edit the file.
For more information on the AspMaxRequestEntityAllowed or the metabase.xml file, see the Microsoft documentation or click the link below.
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