A site contributor reported not being able to upload larger pptx files to their site. There is an Angular UI that interacts via SP2016 on-premise APIs. The user is seeing a continuous uploading message with no result.
Developer tools is showing: POST <%siteurl%> net::Err_FAILED 200 (OK)
When trying to upload the directly to a generic document library, it starts to upload but fails with the following error: "Sorry, your files couldn't be uploaded. The upload might be too large or the server might be experiencing high network traffic."
File size is under 1 GB with the Central Administration > Web Application > General Settings set to allow up to 2 GB. ULS logging does not indicate a specific error surrounding the transaction.
Tested in multiple browsers and in IE mode with the same results. Reviewed similar questions posted here but no answers marked as successful.