IMPORTANT NOTES:
Office for the Web Integration
This Q&A Site targets integrations with the Office Online Server (on-premises) product deployments, not Office for the Web (formerly known as Office 365) product (cloud). For Office for the Web integration questions please direct your posts to the Yammer group provided by the Cloud Storage Partner Program. For more information on that program, please refer to Office Cloud Storage Partner Program.
Make sure you to apply latest Office Online Server Security Patch/Update, here the link https://www.catalog.update.microsoft.com/Search.aspx?q=Office+Online+Server. Please refer here on how to apply the Patch/Update https://learn.microsoft.com/en-us/officeonlineserver/apply-software-updates-to-office-online-server.
WOPI Validator
Before asking a question on this Q&A Site, please run the WOPI Validator to make sure your implementation meets the minimum requirements and is responding correctly to requests. This will eliminate quite a few issues immediately and may resolve the problem you are about to post here.
The WOPI Validator can be found on Github, here: WOPI Validator Core
For Implementers of Protocols
This Q&A Site is for questions about protocol implementation using our Open Specifications documents. If you are not implementing specifically against these documents and cannot formulate your question in the context of these specifications, then likely you need to contact the appropriate product support for assistance.
Microsoft Open Specifications - https://aka.ms/openspecs
Web Application Open Platform Interface Protocol - https://aka.ms/ms-wopi
What are the file sizes supported by Office Online - https://learn.microsoft.com/en-us/microsoft-365/cloud-storage-partner-program/faq/file-sizes
