Office.js web add-in throws HTTP 401 Unauthorized

One of my dev customer, created Outlook Web add-in (using Office.js/JavaScript) and tried calling EWS call (mailbox.makeEWSRequestAsync method). It throws HTTP error 401 for mailbox.makeEWSRequsetAsync() method. They noticed the error or behaviour when they tested with Outlook on the Web and Outlook Web Access for devices. The API call throws, the following HTTP error: “The…


Office 365 Reporting Web Service API developer queries related to response limit, permissions, reports!!

As you aware that the Office 365 Reporting web service enables developers to integrate information on email and spam, antivirus activity, compliance status, and Lync Online activities into their custom service reporting applications and web portals. These are few frequent queries that I come across Office 365 Reporting Web Service API developers – so I…


Gotchas – Microsoft Graph/Outlook REST API throttling, best practices

In recent times, I was working with this customer where they make Graph API calls, Say, GET https://graph.microsoft.com/v1.0/users/YYY@XXX.onmicrosoft.com/mailFolders/inbox/messages?$skip=0&$top=30&$select=bodypreview,categories,conversationid,from,hasattachments,id,isdraft,isread,lastmodifieddatetime,parentfolderid,receiveddatetime,replyto,sender,sentdatetime,subject,torecipients and few other GET (read operations of mail folders/single item handles specifically) and few POST/PATCH calls. They noticed, once the throttling threshold is exceeded, Microsoft Graph limits any further requests from that client for a period of…


Office.js: MakeEWSRequestAsync throws “The request exceeds the 1 MB size limit. Please modify your EWS request”

One of my customer created Outlook Web add-in (Office.js) and when he calls mailbox.makeEwsRequestAsync method. But they got the following error “The request exceeds the 1 MB size limit. Please modify your EWS request”. At the app level, the developer is making the call from web add-in to create a mail item in drafts folder…


Debug: Syncing custom EWS app to an Exchange Server 2010 mailbox receive ErrorServerBusy

When you try to synchronize an Exchange Web Service (EWS)-based application to a mailbox in a Microsoft Exchange Server 2010 environment, you receive an ErrorServerBusy response code and an error message that resembles the following: The server cannot service this request right now. Try again later. This error occurs when the server is busy. Exchange…


Exchange throttling: MAPI application fails with error “The information store could not be opened. [MAPI 1.0 – [MAPI_E_LOGON_FAILED(80040111)]]”

We recently resolved a case where a customer tries accessing Exchange Server 2010 mailboxes (DAG) via their custom Exchange MAPICDO based application. On average 2-3 days once, they’re frequently facing an error “The information store could not be opened. [MAPI 1.0 – [MAPI_E_LOGON_FAILED(80040111)]]” while attempting to connect to Exchange server 2010. After some days of…