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.


2 Answers 2


Saw the same error across multiple sites but not in our lower environments. On a hunch, reached out to network team before opening a Microsoft ticket.

We narrowed down the cause to be a network load balancer web application firewall policy that was throwing a Request length exceeds defined buffer size violation.

Once the policy in violation was modified, the file was able to be uploaded with no errors.


I was facing same issue when trying to upload a 1GB document. My upload limit is 2GB per file. So I was able to resolve it by using Microsoft Edge in Internet Explorer mode. next, you must to clear browsing data: Select All time for Time range and keep the default selections. This made the trick.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.