After deploying a Word Add-in via centralised deployment, it doesn't show up in Word. We used this procedure to deploy the add-in and it lists it there succesfully.
Because we were worried it may be due to something wonky with our own plugin, we then decided to try to deploy the 'Contoso Citations' plugin which is used in the same procedure and screenshots here.
After capturing traffic whenever we press 'Update' under the Add-in Admin Managed dialog, we noticed a connection to Exchange. We then captured the traffic using a proxy and some root certificates, and we found the following call:
POST https://outlook.office365.com/ews/exchange.asmx
<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">
<s:Header>
<RequestServerVersion Version="V2016_10_10" xmlns="http://schemas.microsoft.com/exchange/services/2006/types"/>
<MailboxCulture xmlns="http://schemas.microsoft.com/exchange/services/2006/types">en-US</MailboxCulture>
</s:Header>
<s:Body>
<GetPrivateCatalogAddIns xmlns="http://schemas.microsoft.com/exchange/services/2006/messages"><Client Code="Win32_Word" Version="16.0.0.0"/></GetPrivateCatalogAddIns>
</s:Body>
</s:Envelope>
Which seems to retrieve the catalog from Exchange. This for some reason seems to return a 500 with the following response:
<?xml version="1.0" encoding="utf-8"?>
<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">
<s:Header>
<Action s:mustUnderstand="1" xmlns="http://schemas.microsoft.com/ws/2005/05/addressing/none">*</Action>
</s:Header>
<s:Body>
<s:Fault>
<faultcode xmlns:a="http://schemas.microsoft.com/exchange/services/2006/types">a:ErrorInternalServerError</faultcode>
<faultstring xml:lang="en-US">An internal server error occurred. The operation failed.</faultstring>
<detail>
<e:ResponseCode xmlns:e="http://schemas.microsoft.com/exchange/services/2006/errors">ErrorInternalServerError</e:ResponseCode>
<e:Message xmlns:e="http://schemas.microsoft.com/exchange/services/2006/errors">An internal server error occurred. The operation failed.</e:Message>
</detail>
</s:Fault>
</s:Body>
</s:Envelope>
However, no error dialog or so is shown. It just shows 'No add-ins currently available'. We are running different versions of Office 365 ProPlus (build 1704, 1703 and some others), but all seem to result in a 500 result code. We also have enabled OAuth authentication on our Exchange Mailboxes. Removing all our plugins from the Office 365 admin centre still results in 500's.
Does anybody know why Exchange may be throwing 500's at us, how we can work around this and still deploy the Add-in using the Office 365 Admin Centre? Unfortunately, both deploying using SharePoint or Shared Folders is not a possibility and our Add-in shouldn't be deployed using the store.
