I have a website running in production that uploads files on behalf of users. This functionality has been working for months with only transient network issues.
Past two weekdays (Friday and Monday, virtually no usage over the weekend), all users are getting the standard null reference error whenever they try to upload the file. I'm able to produce this in all our environments. The interesting part is that the graph service itself is returning the error message, this is NOT a null reference exception from the website code.
Here is the request URL:
https://graph.microsoft.com:443/beta/groups/[id]/drive/items/[folderId]:/[filename].[ext]:/microsoft.graph.createUploadSession
The [] and content within are placeholders for the values that are sent. I am using the .NET Graph SDK and have verified that it is properly encoding the file name.
The body of the response from the Graph API is:
{
"error": {
"code": "InternalServerError",
"message": "Object reference not set to an instance of an object.",
"innerError": {
"request-id": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
"date": "2020-02-17T20:10:03"
}
}
}